very good stuff in your channel, i feel one of the best explanation towards architectural, simple english with demo. your channel has very good stuff which will help to master the topics EOD nothing left to miss. Really i understood clearly. since its bit old video, Recent times most of the functions enhanced for VPC EC2, ELB & Lambda added with application(azure function-app). so i would request to do new video on these topics (this video has breaking audio & not clear) i am sure your subscribers gonna watch immediately if you post something. i am already subscribed for all notifications
Thank you so much for the content and hard work you are putting in. They are extremely descriptive. In many of your Videos by the sound of the birds I notice you work early morning just to provide us these awesome content. Hats off.
Sir jee, if our EC2 instances are in private subnets why do we have to select the 2 public subnets when creating the Load Balancer as shown in Step 1: Define Load Balancer ? There isn't any instance in the public subnet for the ELB to route traffic to ? Sorry if you have already answered this question in some other video. I have subscribed to your channel.
We are placing the ELB in public subnet so that it could accept traffic from internet / public and then ELB sends it to Web servers (in private subnets) over private network.
A small doubt what exactly the difference when traffic coming to public or private subnets. When elb load balancer resolves to IP address , once traffic was reached from outside to inside of Amazon data center , regardless of public or private subnet the traffic is routing with in Amazon data center , so my confusion there was no much use of using public or private subnet . Is my understanding correct ??
Thanks, Question: If 'Connection Draining' is time given to instance to finish off existing tasks for a UNHEALTHY instance, This sentence is kind of contradicting as how an UNHEALTHY instance perform pending tasks in specified time (say here 300 seconds)? Please clarify.
Can you please make a video on Internet-facing and internal load balancers? The key differences between the two and the scenarios in which they are used?
Hi Shashank, frankly speaking the only difference between the two is: Internet-facing gets Public IP and internal one does not get Public IP. this further means that internal one cannot accept traffic from internet. Internal load balancers are typically used to expose services which would be consumed with in your VPC (or from on-premise via VPN). Do watch the Networking Playlist completely.
sir ji, 1. you had mentioned that the ELB internally creates instances to manage traffic. Just to expand a little on this, So When this ELB creates the internal instance(i assume its not visible to us ) and it consumes the private IP's too right, Does the internal instance gets created per availability zone or per instance? Coz, I attach an ELB to the instance not to the A.Z ?right? I assume it's something like an agent which gets installed per instance and sort of polling the Domain LB? pls, correct my understanding? 2. Under Load balancers / instances, down the page under availability zone, ELB had created 2 AZ's. whereas I had all 3 of my instances in the same A.Z, though I can edit it and remove the other A.Z, why does it create an another AZ reference point when all my instances are in only one AZ? pls assist 3. Under health check, the ping target, I gave the path index.html. let's assume I have 2 instances and if I want the index.html to reside in a different location for all the 2 instance, let's assume for the 1st one, it's under var/www/HTML and for the second one if its under var/www ..does the ping target as the intelligence to check the file irrespective if its location?
Thanks a lot for your kind words. I request to spread the videos more and more so that people and friends could get benefited. Please Subscribe to our blog for exercises --- aws-tutorials.blogspot.in/ (LIVE Session details are updated here) Like our FB page to know the announcements --- fb.me/AWStutorials - please write about us and tag our page on FB/LinkedIn. LinkedIn - in.linkedin.com/in/knowledgeindia Subscribe to our RUclips channel to get alerted about new videos --- ruclips.net/user/knowledgeindia Our Twitter handle is twitter.com/knowledge_india
Thanks a lot bro. Please share the videos. Also, i am starting an Online and Classroom training for people who want to move forward quickly.. Please see below for details, i am sure you will like it as you have liked my videos till now.. Details are given here --- aws-tutorials.blogspot.in/2017/06/aws-solutions-architect-associate.html aws-tutorials.blogspot.in/2017/06/aws-sysops-administrator-associate.html Please let me know for any doubts you might have... :)
hi sir greetings to you. your videos are perfect and in detail . Can you please guide me in sequence which topics to go thru first and then what next . so that there is a proper flow. I mean to say step by step which topic first and then what next. like for example you have made so many videos on AWS . So for a fresher which is the 1st one and which one is the 2nd one and so on. so that we can learn in a proper sequence
I did this many times. But the instances in public subnets are attached to ELB and in-service. But the one which is in private subnet shows out-of-service. What is the solution for this? Do we need a NAT gateway?
I recently hit a hurdle when exposing a demo website restricted by IIS Windows Authentication using an Amazon Web Services (AWS) Elastic Load Balancer (ELB). The symptoms were that the website requested the credentials, as expected, but would then continue to request these for every hit of the website resulting in an unusable user experience of countless logins. The problem appears to be in the way the ELB forwards on the credentials. To overcome this issue simply changes the ELB listener from the default Load Balancer and Instance Protocol of HTTP to TCP. The problem will then disappear. Could you please let me know with the above case that can we also use NLB to overcome with this issue. if not than please explain why it is behaving propery with classic LB and not with an ALB.
Hi .. Great Stuff. Thanks for sharing Knowledge. I have one question. if we launch both instances in private subnet. how we can access them and configure them?
Very nice video, Thanks for posting it. I have a some doubts, kindly clarify. 1. How ELB determines when to scale up(create new instance) ? Is the logic of creating new instance is internal to classic load balancer or we can provide specific instructions on when to scale up , like we do while creating application load balancing using auto scaling groups ? 2. How ELB chooses under which subnet it should create the new instance ? Can we see the new instances once it is created under "Load Balancer -> Instances" section. 2. As per my understanding the routing in classing load balancing is taken care in round robin fashion, Can that be controlled by user like choosing a different algorithm for routing ?
1. It's internal. 2. you cannot see, but you can know it based on the IPs consumed from the subnet. Mostly, it would be 2 instances created (1 in each subnet). Because ELB is managed service, pricing would never depend on internal instances created. Please watch ELB pricing video as well. 3. User can not specify a custom one. If you have got benefited, please share the video and consider writing about our videos on LinkedIn. Thank you.
Hi ,. Can we use Route 53 instead of ELB ? to save cost if it can or any other services to distribute 100% traffic to EC2-1 in AZ1 and if it goes down then only we can distribute / route traffic to another EC2-2 in AZ2 .... ( If Only two EC2 are available one in each AZ ). Please suggest as this is a real time requirment.
i have tried this but it didnt work, does the private subnet have to have a gateway or something? I am launching instances, putting them in private subnet, put load balancer in same AZ public subnet but healthcheck keeps failing
Hi, you have created two public sub nets. But ip addresses from 10.0.0.0/27 to 10.0.0.31/27 in one sub net and another is from 32 - 63. But it should be total 32 hosts available not 64. Because 2^ (32-27) = 2^5 = 32. Please clarify whether I am wrong or right.
at 6:55 you can see, the public subnets are smaller than private subnets. Public ones are /27 and hence 32 IPs in each public subnet. Please watch our VPC video, if you need more calrity with CIDR - ruclips.net/video/tD9vDv0uyI8/видео.html
One thing is still not clear, my question is ...as per your diagram...if i have chosen public subnet to launch ELB then how it can consume the private IP to launch the internally created instances...ideally it should be consuming the public ip's...please correct me if i am wrong here.
Knowledge India so it means if its in a public subnet it will consume public ip only and if elb is in a private subnet then it will consume private ip only...
Thanks for the explanation on this video. It was clear and precise. My only question is what was the inbound protocols set up on the security group assigned to the ELB? Thanks
Thanks for these wonderful videos and it really helped to understand AWS concepts! As you mentioned that the ELB internally creates instances to manage traffic. How these ELB instance are able to talk to private ec2 instance without NAT gateway or NAT instance though both ELB and ec2 instance are in same VPC? Also, as per your video, I tried to configure my ping path in my private ec2 instance as /var/www/health.html and then I configured my ELB. Health of ELB is always outOfService. Please guide me if I have something wrong.
Your path should be a valid URL on the EC2 instance. Another instance cannot access filesystem URL e.g. /var/www/health.html As ELB is also with in the VPC (see the creation of ELB) and all instances with in a VPC can talk to each other. hence, ELB is able to talk to private instances using private IP.
Does Public Subnets are Inself an EC2 insatance ? I want to create Zuul as API gateway and Load Balancer so i it possible that I can deploy Public subnets in Zuul and Private for SPring Boot and Other Microservices ?
Hi Sir, i like your videos and way of your concept clearing. I appriciated. Sir i want to know one thing you are using this website ami in ELB. I already done ELB as you explain in video. And elb is working but how can i check ip of elb as you shown on your page after refresh ip on your page is changes. This is coding in html file or anything special. And one thing i want to know. How you connect images and css from s3 bucket.
Mohit, it is the IP of the instance and not ELB. You can write a script using any server side language like JAVA, PHP, ASP to show a machine'e IP. For S3 usage, see the videos on CloudFront, i have explained the same. Please don'w forget to share with your friends all the videos you like.. Please recommend us on LinkedIn, write a Testimonial if you learned the concept and your questions are answered -- in.linkedin.com/in/knowledgeindia Please help us to spread the knowledge to others as well; please SUBSCRIBE to our RUclips Channel & LIKE and SHARE the videos if they helped you to learn. We have many more videos on AWS topics, these are organized in playlists here -- ruclips.net/user/knowledgeindiaplaylists You can subscribe to our blog to receive useful AWS related content -- aws-tutorials.blogspot.com
1. Try to make an image from amazon linux with Apache - httpd installed on it. 2. Use this AMI to create 2 instances. 3. Start these 2 instances and link them in ELB. 4. Apache index.html page is at - /var/www/error/noindex.html 5. Perform ifconfig on both instances. 6. Take the private IP on both instances. 7. Perform `traceroute "Private Ip" > noindex.html` on both nodes. 8. Now open the ELB using DNS name and keep refreshing. 9. Page will keep switching IP of both instances , hence working as Round Robin. Hope this helps.
Sir, i passed my AWS CSA exam last week. Thanks to your videos. I had one question for you regarding ELB if you can pls advise? In a typical setup wherein we have ELB and EC2 instances in pvt subnet, how can we whitelist or allow specific ip-addresses and deny/block the rest ? The requirement is to allow only known ip addresses to access our web application in ELB and deny the rest. Is the correct answer to do this via NACL in which the ELB resides or can we just add a security group tied to our EC2 instances ? What about allowing HTTP X-forwarder within our application server config file at the OS level of EC2?
Hellos... No doubt the video is awsum... But I have a bit issue. I have tried several times creating load balancer using ec2 instance created with private subnets. I have followed the exact method used in video. While creating load balancer, I have selected private subnet ec2-instances and under subnet tab I have selected both the public subnets. But still 0 of 2 instance in service gets showed. And when I launch load balancer using public subnet ec2-instance and public subnet in subnet tab, I am successfully able to launch load balancer. Could you please help me in that? And also why you used private subnet to create ec2-instance, when we had public subnet also with us??
Sir, I have one query, need help.. What does these 4 parameters indicate and the values with in them..(in ELB Configuration) Timeout 5 seconds ?? Interval 8 seconds ?? Unhealthy threshold 2 ?? Healthy threshold 3 ?? Thank you in advance, i will wait for your response sir. Regards
1) The instances what you have used server-1 and server-2, Can we ssh and connect? 2) The number of instances of LB are equal to number of AZs I configures right? If I use 4 AZs for LB, then 4 instances of LB will be running right?
1) they are private. you can via a Bastion host / jumpbox. 2) yes Please support us by sharing our videos and channel on LinkedIn/FB/Twitter, to bring more such AWS videos.
Question and correcting my understanding time !! ---------------------------------------------------------------------- 1. ELB cannot be attached to both public and private subnet at the same time, right? So the 1st line of defence [in fact after the sec group and ACL ] would be the public Subnet right? coz, typically in the private subnet, we would have hosted D.B or some critical application wherein we don't want any public to have direct access? 2. We can still have a separate ELB for private subnet traffics too? 3. If in case if we have only one ELB which is associated with the Public subnet, any flow to the private subnet from the public subnet will also be load balanced if we enable CROSS ZONE LOAD BALANCING? 4. And just to clear up certain terminologies, Do we really keep an ELB in public or private !! or do we associate the respective public and private instances with the ELB? like always thank in advance :) 5. One subnet = one ACL, [Cannot be associated with more than one ACL ] But one ACL can be assocated with multisubnets right ?
1. ELB cannot be attached to both public and private subnet at the same time, right? So the 1st line of defence [in fact after the sec group and ACL ] would be the public Subnet right? coz, typically in the private subnet, we would have hosted D.B or some critical application wherein we don't want any public to have direct access? Ans: That is right. You make ELB either in Public or Private subnet and not both. Public ELB can be placed in front of Web-tier. Private ELB can be placed between Web-tier and App-tier. 2. We can still have a separate ELB for private subnet traffics too? Ans: Yes 3. If in case if we have only one ELB which is associated with the Public subnet, any flow to the private subnet from the public subnet will also be load balanced if we enable CROSS ZONE LOAD BALANCING? Ans: Cross zone load balancing has to deal with balancing of data between 2 AZs (irrespective of Public or private subnets). Additionally, only the instances registered to ELB would receive traffic via ELB. 4. And just to clear up certain terminologies, Do we really keep an ELB in public or private !! or do we associate the respective public and private instances with the ELB? Ans: We first create ELB in Public or private subnets (based on the need) and then register the instances which need to receive traffic from that ELB. like always thank in advance :) 5. One subnet = one ACL, [Cannot be associated with more than one ACL ] But one ACL can be assocated with multisubnets right ? Ans: It's NACL not ACL. Yes, one subnet can have only one NACL, but one NACL can be attached to multiple subnets. Some of these things are easily verifiable from console itself, while we do the practicals. Keep learning.
while going through the steps to create the ELB, configure security settings in the ELB setup asks for the certificates. How can i address this? seems its a new feature i guess the reason was being the HTTPS port option was selected. if only the HTTP alone is used. the issue would not be there. thank you so much
Thanks for this Vedio its really helpful ! one question thought, How those private instance were accessing internet as NAT is option is not enabled it seems in your demo route table ??
Now I understood. You have created VPC with CIDR range 10.0.0.0/24. So total 2 ^ (32-24) = 256 hosts available in this VPC. Among of them you want to assign 64 hosts as public sub-net so CIDR rang is /27 (32 hosts in each AZ). and 64 hosts in each private subnet ( total 128 hosts in private subnet. 2 AZ * 64 ). Please let me know whether my understanding is wrong or right.
please see carefully - 10.0.0.0/27 is for one public subnet which means one public subnet has 32 IPs, same for other public subnet. Read my reply on other comment carefully and evaluate the IPs for all 4 subnets, you will understand.
yes. but you should not have edited the comment, rather written a reply .. anyway.. Please share the video & channel with your friends, if it helped you in learning..
As explained in LIVE Session today, it affects the distribution mechanism. TCP - simple round robin between instances HTTP/HTTPS - instances which has least open requests, gets the next request.
good explanation. thanks. just 1 thing, the SG for the private instances could have be more locked down to only accept traffic from the public subnet, correct? thanks again.
I too appreciate with million of Thanks. My question is if we create production instance with private subnets than we don't get public ip address. how can we login the instance without public ip address?
Thanks Siva. In such a case we use Bastion Host (or Jumpbox) in Public subnet. Jumpbox is just a simple small Windows/Linux machine in Public Subnet, so we first login to that Jumpbox; and then we can connect the instances in Private Subnet over the private IP. Do not forget to SHARE the videos with your friends.
Hi, what were the Inbound and OutBound rules for the security group associated with EC2 and Classic ELB, Can you please include them in the video and how did you create VPC, using Wizard?
Very helpful information. Thank you! But when i try to browse the Public DNS/public IP in the browser am getting time out error like this (This site can’t be reached took too long to respond.) could you please explain, what could be the reason, Thank You.
Quick question...There are lot of posts online which talk about need to open ephemeral ports for the ec2 instances else external clients won't be able to connect to our website. How come you have not defined / mentioned any ephemeral ports & yet you are able to access your website over internet? Thanks in advance
Neeraj, Ephemeral ports will come into picture in case of NACL outbound rules. As the clients could be having different types of OS, typically all the Outbound rules are allowed in NACL. Hence, we don't need to do anything. Moreover, Security Groups are stateful and hence nothing to worry. Please see other videos, i have explained most of these things in detail.. Please don't forget to share with your friends all the videos you like.. Please recommend us on LinkedIn, write a Testimonial if you learned the concept and your questions are answered -- in.linkedin.com/in/knowledgeindia Please help us to spread the knowledge to others as well; SUBSCRIBE to our RUclips Channel & LIKE and SHARE the videos if they helped you to learn. We have many more videos on AWS topics, these are organized in playlists here -- ruclips.net/user/knowledgeindiaplaylists You can subscribe to our blog to receive useful AWS related content -- aws-tutorials.blogspot.com
Please try to listen from 5:00 again. Webservers are in private only. In Public, i have shown internal instances of ELB. I would request you to SUBSCRIBE our CHANNEL and look at our playlists for SA & SysOps here -- ruclips.net/video/ywHFXfuJoSU/видео.html &&& ruclips.net/video/UFSH-KuDGj8/видео.html Connect with me on LinkedIn to read interesting important AWS updates --- www.linkedin.com/in/knowledgeindia Please follow my FB page fb.me/AWStutorials & Twitter - twitter.com/#!/knowledge_india And for AWS exercises, you can refer our blog -- aws-tutorials.blogspot.com/
Hi, Can someone clarify why do we have to create two separate web-servers? What if we have a single web-server then can't we have scalability? As I thought if I attach websever to ELB then it will automatically scale up and down. Could someone please clarify this confusion?
@@knowledgeindia Thank you for reply. I have check auto-scaling video and my understanding + questions are written below. 1- In the current video is explaining the scenario when we are handling scalability oursleves. 2- For auto-scaling: Create an EC2 instance and install the software / application on it. I am not very sure if we can use this instance directly in Launch configuration or we must create an AMI. Would be helpful if you can clarify. 3- Launch a configuration that actually tells AWS what type of instances are required to be created in case of scale up operation. 4- Create Auto-scale group to define conditions when to scale up and down + what is min and max numbers of instances Let me know if my understanding is correct. Now I am wondering what if I need to modify my application ( enhancements / bug fixes etc ). What will be the steps to do it: 1- Create new AMI and then modify the existing configuration or launch a new one? 2- In case we must have to launch a new configuration then attach this one with the existing Auto-scaling group?
Answers here. 1.yes 2. you need to create AMI. because in Launch config, it asks you to select AMI. 3. yes. 4. term should be scale out and scale in. correct understanding. 1. yes. create a new launch config from the new AMI. 2. the update this launch config ID to the ASG. I suggest you should do practical as well, so you will not have above doubts.. :) Please share with your friends, if you like our videos..
@@knowledgeindia Thanks for replying. Now i have this basic understanding and image in my mind so time to move on to the practical. I will for sure suggest your channel to my friends and colleagues.
Hi , If i deploy a firewall ,before the ELB. The ELB loadbalnces traffic in 2 AZ. So incoming traffic (from internet goes from) NAT->FIREWALL(Outside Interface) ->ELB-> AZ1 / AZ2 for outgoing traffic, the Server in AZ2 needs to reach the FIREWALL(inside) interface. How can we route the traffic from server in AZ2 to FW Inside interface?
You have few misconceptions as i observe from above statement. Please see other videos in playlist related to VPC, ELB, NAT etc. you will be able to understand.
sirji !! While i was working with the ELB's, I came across this scenario where I was able to add an instance [One instance ] to 2 ELB's . I found that little strange, hence reaching out to you to ask, if that behaviour was expected and can you help me with a live example.
Is it expected or not, is a different question.. But, technically this is possible. Think on a a machine there are 2 processes running (IIS on 80 and Tomcat on 8080). 2 ELBs could be sending traffic to these different processes.
ohh ..so when defining the load balancer, There is this listener configuration for load balancer and Instance protocol, So the INSTANCE PROTOCOL is the place where we can choose a different port for different services? right?
Hello Knowledge India, I have deployed the nextcloud application in AWS. Below is the architecture 1) Created a VPC with 2 public and private subnet 2) Hosted nextcloud app in ubuntu in 2 EC2 instances in private subnet using a jump server(windows) in public subnet 3) Configured the RDS(Maria DB) to connect to NextCloud app 4) Created a Classic Load Balancer and configured 2 public subnets and added 2 running EC2 instances. 5) Created a proper security groups to access the application thro load balancer Application is running fine and have checked the requests are going to both the servers. Now I want to 1) Add both these Ubuntu servers into Auto Scaling group, so that when the user requests increases, few more EC2 instances boots up to handle the load. 2) To have lambda function to get db snapshot everyweek into S3. Can you please help me
1. Create an auto scaling group (video is there) and then in that ASG, there will be an option to add already running instances to it. 2. See the video of lambda function . write a python script. in RDS, there would be createSnapshot action; use that & write it.
An ELB will always always have to be placed in a Public Subnet. You cannot, or rather should not put an ELB inside a private Subnet. REASON: The purpose of an Internet-Facing ELB is that it can forward traffic from Internet to all EC2 instances which are registered to it. And Private Subnets do not have Internet Gateways attached to it. Meaning they cannot recieve or send traffic to the internet(Unless they have a NAT attached to it). So when you put an Internet-Facing ELB in a private subnet, it will neither be able to recieve nor send traffic. Did I answer your query ?
I have a doubt here sir. There are two subnets. Are subnets only ip addresses? Or We have instances in subnets? As far as i can understand in the example there are two instances already mapped to the two subnets and apart from that te ELB internally launches two instances! Can you please clarify on this! I took many examples can't understand! #sastrite
hi dear, i have a doubt, that is i have one instance is for only front end and another instance is for backend. and i want to add 2 backend instances into load balancer. how will i achieve this. please help me.
@@knowledgeindia sorry, i want to attach 2 backend instances to load balancer. and not attaching front end instance to load balancer. front end is open to public but back end is not open for public. so in this case how i will achieve that.
I have tried doing this but my both the instances failed health check up...could please help me in resolving this...like where I should check to pass the health check up
I am using linux machine as a ec2 instance and also given user data same as given by you while creating instance. I tried to all the things same as done by you. Could you please help configuring SB for elb instance and for linuc ec2 instances. Might that would help me to pass the health check up for instances.
is there any requirement of NAT Gateway? I know that if my Instances are in private subnet and I want to access the internet from that private instances then NAT gateway is required. I am asking this question because my both private instances are out of service constantly and showing "instance has failed at least the UnhealthyThreshold number of health checks consecutively." error. Please Help me.
Have your instances got the web server installed and the health check file is correctly placed? Also, review the security group to allow traffic from load balancer
you go to a region and then create ELB. You need to choose subnets in which you want to place it. i have shown the same in the video. An ELB can not span across regions. Please share the videos. Also, i am starting an Online and Classroom training for people who want to move forward quickly.. Please see below for details, i am sure you will like it as you have liked my videos till now.. Details are given here --- aws-tutorials.blogspot.in/2017/06/aws-solutions-architect-associate.html aws-tutorials.blogspot.in/2017/06/aws-sysops-administrator-associate.html Please let me know for any doubts you might have... :)
*Sorry Sir, but i am unable to create as in LOAD BALANCER , it is showing that the health checks are OUT OF SERVICE and according to this they are telling that my ec2 instance is not registered ? Will you please help me to troubleshoot this!*
yes sir ! i have checked them ...even I have used Bootstrap for HTML file i think so there might be different problem as i am not able to create any of the load balancer now... Though... thanku sir!
Hello Sir, Need one clarity, what is the SG rules (inbound) of your ELB in above example. I tried all same but the instances are continuously showing out of service. My Set Up : 2 Linux Instance in prv subnet that has apache web server running.. Both instance's have same SG that is configured to accept traffic over port 80 and 443 from "anywhere" My query is what is inbound rule of ELB in public subnet. Thank you
for ELB it should be 80 or 443 from anywhere. for EC2, it should be 80 from ELB SG. If instances are not showing healthy in Target Group, still go ahead & check by hitting Load Balancer URL.
Great Video! I completed the setup as you have shown and shutdown both the instances which are in private subnets. When I do the nslookup for the loadbalancer DNS. I see a public IP associated with it. Is this the public IP of that instance which was created (internally) when loadbalancer was created?
Yes, as you can see there is no so option. Also, always read about pricing of any service in documentation. It helps a lot. Don't forget to share the video :)
Yes, as you can see there is no so option. Also, always read about pricing of any service in documentation. It helps a lot. Don't forget to share the video :)
can we create ELB using free tier account? If we add two instances in ELB (windows & linux) with web servers(IIS and apache) installed. As we will only use the DNS of ELB to access these services, how the ELB will know which service(IIS or APache) we are trying to access? because DNS address will always be the same.
Please see the Free tier video. Yes you can create ELB as part of free tier. The service gets decided by the port you choose in Listener creation in ELB. Also, ideally you will keep same type of instances behind an ELB. E.g. all windows or all linux.
@@knowledgeindia health is Ping Target HTTP:80/index.html Timeout 5 seconds Interval 30 seconds Unhealthy threshold 2 Healthy threshold 3 security group of my private instances is allowing access from the security group of Load Balancer nat gateway is set to allow internet access for private subnets in Private rout table IGW is set for public for public subnets in main route table I am not able to figure out where i am making a mistake
Thank you for your reply. Sir i have configured with the security group as shown in the video with port 80 and port 22 open to 0.0.0.0/0 still i am facing the same error. i have not configured the windows instance i have gone with Linux instance. please let me know as what to do.
its running on both 80 and 22. my public instance is running healthy and it in Service, the private instance is showing OUT of Service even after so many rechecks.
It could be launched in Public or private. Depending on use case, we do it. Please read the documentation and do practical in parallel to understand well.
Thanks for the videos. Does WEBSERVER mandatory for ELB to work ? I am trying to setup 1-ELB(classic) and 2-EC2 instances on the private subnet(same AZ). The EC2 instances have application running on IBM WebSphere. App1 URL : ecserver1:9080/app-war-1.0-SNAPSHOT-websphere/ContextName/login.jsp App2 URL : ecserver2:9080/app-war-1.0-SNAPSHOT-websphere/ContextName/login.jsp I have created load balancer with requried SG [listener port open for 9080/80]. Pingpath set as "/app-war-1.0-SNAPSHOT-websphere/ContextName/login.jsp", http : 9080 When I am accessing LB URL - testelb:80/app-war-1.0-SNAPSHOT-websphere/ContextName/login.jsp am getting 503 error. Do I need to have WEB SERVER infront for ELB to work ?
Thanks for the reply. I should have mentioned that I have already registered the instances to ELB. Does ELB work with the WAS(application installed in IBM WAS 9.0 in this case)
Yes it should work. Check the security group of EC2 instances. Make 9080 open in inbound. Also, see if health checks from ELB are successful and both instances are shown healthy in ELB.
for those who have speed catch, proabably a good video. but for me i have to say sorry more than understanding, getting more confused. which are you clicking fast here and there man.
Your voice is hardly understandable during demo. My suggestion is - when you are any throat problem, its better not to record, as it is not helping the audience. :)
Two words : crisp and lucid. Great Stuff !!!! Kudos to you guys.
Thanks a lot. Please support us by sharing our video and channel with your friends..
Simply amazing!!! You are the best!!!
Best ELB explanation and hands on on youtube .Best of luck for future.
Thank you so much 😀
Do check our playlists for more such awesome content.. You can share and help us.
Thanks a lot... I was blocked by LB for a while. Your video saved my life :)
please do share with your friends as well.. :)
Really your videos are clear as crystal...thanks for your videos ..need more on Devops stuffs as well
Please share with friends if this has helped you..
Knowledge India can we have Devops videos
yes will do.
I have not seen such crisp and to the point explanation. Great work guys!
Thanks a lot. Please do share with your friends..
very good stuff in your channel, i feel one of the best explanation towards architectural, simple english with demo.
your channel has very good stuff which will help to master the topics EOD nothing left to miss.
Really i understood clearly. since its bit old video, Recent times most of the functions enhanced for VPC EC2, ELB & Lambda added with application(azure function-app). so i would request to do new video on these topics (this video has breaking audio & not clear)
i am sure your subscribers gonna watch immediately if you post something. i am already subscribed for all notifications
Thank you so much for the content and hard work you are putting in. They are extremely descriptive. In many of your Videos by the sound of the birds I notice you work early morning just to provide us these awesome content. Hats off.
akshay gupta thanks Akshay for your kind words. May I request you to share the videos with your friends or on social media!
Knowledge India yes sure.. I personally advice my friends to watch your channel. You have been a great help to many people. May you grow big.
Excellent explanation on ELB thanks
really simple and best explanation. appreciated
Sir jee, if our EC2 instances are in private subnets why do we have to select the 2 public subnets when creating the Load Balancer as shown in Step 1: Define Load Balancer ? There isn't any instance in the public subnet for the ELB to route traffic to ? Sorry if you have already answered this question in some other video. I have subscribed to your channel.
We are placing the ELB in public subnet so that it could accept traffic from internet / public and then ELB sends it to Web servers (in private subnets) over private network.
A small doubt what exactly the difference when traffic coming to public or private subnets.
When elb load balancer resolves to IP address , once traffic was reached from outside to inside of Amazon data center , regardless of public or private subnet the traffic is routing with in Amazon data center , so my confusion there was no much use of using public or private subnet .
Is my understanding correct ??
How placing ec2 instances in private subnet provides more secured traffic ??
Great Work , very much appreciated
Pls attach the file aswell in the description..so that we can download it
Good Explanation.I am referring your videos to learn aws
Great. You can join our LinkedIn group as well
Thanks, Question: If 'Connection Draining' is time given to instance to finish off existing tasks for a UNHEALTHY instance, This sentence is kind of contradicting as how an UNHEALTHY instance perform pending tasks in specified time (say here 300 seconds)? Please clarify.
great ..well explained...i am looking for application ELB
Nice tutorial. kindly make a tutorial on application load balancing.
good explanation. I like most of the KI videos
thanks Abhishek. Please share our videos with your friends as well.
Can you please make a video on Internet-facing and internal load balancers? The key differences between the two and the scenarios in which they are used?
Hi Shashank,
frankly speaking the only difference between the two is: Internet-facing gets Public IP and internal one does not get Public IP. this further means that internal one cannot accept traffic from internet.
Internal load balancers are typically used to expose services which would be consumed with in your VPC (or from on-premise via VPN).
Do watch the Networking Playlist completely.
sir ji,
1. you had mentioned that the ELB internally creates instances to manage traffic.
Just to expand a little on this, So When this ELB creates the internal instance(i assume its not visible to us ) and it consumes the private IP's too right,
Does the internal instance gets created per availability zone or per instance? Coz, I attach an ELB to the instance not to the A.Z ?right?
I assume it's something like an agent which gets installed per instance and sort of polling the Domain LB? pls, correct my understanding?
2. Under Load balancers / instances, down the page under availability zone, ELB had created 2 AZ's.
whereas I had all 3 of my instances in the same A.Z, though I can edit it and remove the other A.Z, why does it create an another AZ reference point when all my instances are in only one AZ? pls assist
3. Under health check, the ping target, I gave the path index.html.
let's assume I have 2 instances and if I want the index.html to reside in a different location for all the 2 instance, let's assume
for the 1st one, it's under var/www/HTML and for the second one if its under var/www ..does the ping target as the intelligence to check the file irrespective if its location?
Answer is written here --- aws-tutorials.blogspot.in/2017/04/understanding-elb-in-depth-query-from.html
Very helpful information. Thank you!
Thanks a lot for your kind words. I request to spread the videos more and more so that people and friends could get benefited.
Please Subscribe to our blog for exercises --- aws-tutorials.blogspot.in/ (LIVE Session details are updated here)
Like our FB page to know the announcements --- fb.me/AWStutorials - please write about us and tag our page on FB/LinkedIn. LinkedIn - in.linkedin.com/in/knowledgeindia
Subscribe to our RUclips channel to get alerted about new videos --- ruclips.net/user/knowledgeindia
Our Twitter handle is twitter.com/knowledge_india
Great Work Knowledge India.
Keep It up!!
Thanks a lot bro. Please share the videos. Also, i am starting an Online
and Classroom training for people who want to move forward quickly..
Please see below for details, i am sure you will like it as you have
liked my videos till now..
Details are given here ---
aws-tutorials.blogspot.in/2017/06/aws-solutions-architect-associate.html
aws-tutorials.blogspot.in/2017/06/aws-sysops-administrator-associate.html
Please let me know for any doubts you might have... :)
hi sir greetings to you. your videos are perfect and in detail . Can you please guide me in sequence which topics to go thru first and then what next . so that there is a proper flow. I mean to say step by step which topic first and then what next. like for example you have made so many videos on AWS . So for a fresher which is the 1st one and which one is the 2nd one and so on. so that we can learn in a proper sequence
Please check our playlists and pickup Sysops playlist
I did this many times. But the instances in public subnets are attached to ELB and in-service. But the one which is in private subnet shows out-of-service. What is the solution for this? Do we need a NAT gateway?
Excellent video bro. Keep up the good work.I'm referring only your video for AWS.
Thanks Chandra. Please support us and do share with your friends on Social platforms.
Knowledge India : yes ...have already shared with my friends. 😊
If you have done any DOCKER, ANSIBLE tutorial kindly provide me the links.👍👏
While creating ELB..you selected a elb security group...what are the inbound rules of that security group.
Is it just allowing http 80 0.0.0.0/0 .
This is awesome demo thank you so much 👍👍👌❤
Please do share with your friends .. Thank you...
What is difference between ELB & Auto scaling ? They both are doing same task
I recently hit a hurdle when exposing a demo website restricted by IIS Windows Authentication using an Amazon Web Services (AWS) Elastic Load Balancer (ELB). The symptoms were that the website requested the credentials, as expected, but would then continue to request these for every hit of the website resulting in an unusable user experience of countless logins.
The problem appears to be in the way the ELB forwards on the credentials.
To overcome this issue simply changes the ELB listener from the default Load Balancer and Instance Protocol of HTTP to TCP. The problem will then disappear.
Could you please let me know with the above case that can we also use NLB to overcome with this issue.
if not than please explain why it is behaving propery with classic LB and not with an ALB.
Not able to understand how the public instance will automatically launched from ELB, you said @5:23 in this session. ?
Hi .. Great Stuff.
Thanks for sharing Knowledge.
I have one question. if we launch both instances in private subnet. how we can access them and configure them?
thanks. you need to launch Bastion host in public subnet. Look at our VPC playlist to learn it all..
Very nice video, Thanks for posting it.
I have a some doubts, kindly clarify.
1. How ELB determines when to scale up(create new instance) ? Is the logic of creating new instance is internal to classic load balancer or we can provide specific instructions on when to scale up , like we do while creating application load balancing using auto scaling groups ?
2. How ELB chooses under which subnet it should create the new instance ? Can we see the new instances once it is created under "Load Balancer -> Instances" section.
2. As per my understanding the routing in classing load balancing is taken care in round robin fashion, Can that be controlled by user like choosing a different algorithm for routing ?
1. It's internal.
2. you cannot see, but you can know it based on the IPs consumed from the subnet. Mostly, it would be 2 instances created (1 in each subnet). Because ELB is managed service, pricing would never depend on internal instances created. Please watch ELB pricing video as well.
3. User can not specify a custom one.
If you have got benefited, please share the video and consider writing about our videos on LinkedIn. Thank you.
Thank you very much providing the answers. I will definitely share it.
explained clearly. thanks.
Please SUBSCRIBE & SHARE and don't miss any updates..
Can you please share how to create a sample webpage that you have shown in the video?
Hi ,. Can we use Route 53 instead of ELB ? to save cost if it can or any other services to distribute 100% traffic to EC2-1 in AZ1 and if it goes down then only we can distribute / route traffic to another EC2-2 in AZ2 .... ( If Only two EC2 are available one in each AZ ). Please suggest as this is a real time requirment.
i have tried this but it didnt work, does the private subnet have to have a gateway or something? I am launching instances, putting them in private subnet, put load balancer in same AZ public subnet but healthcheck keeps failing
Hi, you have created two public sub nets. But ip addresses from 10.0.0.0/27 to 10.0.0.31/27 in one sub net and another is from 32 - 63. But it should be total 32 hosts available not 64. Because 2^ (32-27) = 2^5 = 32. Please clarify whether I am wrong or right.
at 6:55 you can see, the public subnets are smaller than private subnets. Public ones are /27 and hence 32 IPs in each public subnet.
Please watch our VPC video, if you need more calrity with CIDR - ruclips.net/video/tD9vDv0uyI8/видео.html
One thing is still not clear, my question is ...as per your diagram...if i have chosen public subnet to launch ELB then how it can consume the private IP to launch the internally created instances...ideally it should be consuming the public ip's...please correct me if i am wrong here.
it takes both.
Knowledge India so it means if its in a public subnet it will consume public ip only and if elb is in a private subnet then it will consume private ip only...
Thanks for the explanation on this video. It was clear and precise. My only question is what was the inbound protocols set up on the security group assigned to the ELB? Thanks
It would be TCP 80 from anywhere
Thanks for the excellent video...Can you please upload the demo for application load balancer as well
Sure. Will do soon. SUBSCRIBE and remain alerted.
need application load balancer demo
its available on the channel now.
its available on the channel now.
Thanks for these wonderful videos and it really helped to understand AWS concepts!
As you mentioned that the ELB internally creates instances to manage traffic. How these ELB instance are able to talk to private ec2 instance without NAT gateway or NAT instance though both ELB and ec2 instance are in same VPC?
Also, as per your video, I tried to configure my ping path in my private ec2 instance as /var/www/health.html and then I configured my ELB. Health of ELB is always outOfService. Please guide me if I have something wrong.
Your path should be a valid URL on the EC2 instance. Another instance cannot access filesystem URL e.g. /var/www/health.html
As ELB is also with in the VPC (see the creation of ELB) and all instances with in a VPC can talk to each other. hence, ELB is able to talk to private instances using private IP.
Does Public Subnets are Inself an EC2 insatance ? I want to create Zuul as API gateway and Load Balancer so i it possible that I can deploy Public subnets in Zuul and Private for SPring Boot and Other Microservices ?
Why the load balancer is launched in public subset. Can we launch load balancer and instances in private subnets..
Hi Sir, i like your videos and way of your concept clearing. I appriciated. Sir i want to know one thing you are using this website ami in ELB. I already done ELB as you explain in video. And elb is working but how can i check ip of elb as you shown on your page after refresh ip on your page is changes. This is coding in html file or anything special. And one thing i want to know. How you connect images and css from s3 bucket.
Mohit, it is the IP of the instance and not ELB. You can write a script using any server side language like JAVA, PHP, ASP to show a machine'e IP.
For S3 usage, see the videos on CloudFront, i have explained the same. Please don'w forget to share with your friends all the videos you like.. Please recommend us on LinkedIn, write a Testimonial if you learned the concept and your questions are answered -- in.linkedin.com/in/knowledgeindia Please help us to spread the knowledge to others as well; please SUBSCRIBE to our RUclips Channel & LIKE and SHARE the videos if they helped you to learn. We have many more videos on AWS topics, these are organized in playlists here -- ruclips.net/user/knowledgeindiaplaylists
You can subscribe to our blog to receive useful AWS related content -- aws-tutorials.blogspot.com
1. Try to make an image from amazon linux with Apache - httpd installed on it.
2. Use this AMI to create 2 instances.
3. Start these 2 instances and link them in ELB.
4. Apache index.html page is at - /var/www/error/noindex.html
5. Perform ifconfig on both instances.
6. Take the private IP on both instances.
7. Perform `traceroute "Private Ip" > noindex.html` on both nodes.
8. Now open the ELB using DNS name and keep refreshing.
9. Page will keep switching IP of both instances , hence working as Round Robin.
Hope this helps.
Great work...
Sir, i passed my AWS CSA exam last week. Thanks to your videos. I had one question for you regarding ELB if you can pls advise? In a typical setup wherein we have ELB and EC2 instances in pvt subnet, how can we whitelist or allow specific ip-addresses and deny/block the rest ? The requirement is to allow only known ip addresses to access our web application in ELB and deny the rest. Is the correct answer to do this via NACL in which the ELB resides or can we just add a security group tied to our EC2 instances ? What about allowing HTTP X-forwarder within our application server config file at the OS level of EC2?
Hellos... No doubt the video is awsum... But I have a bit issue. I have tried several times creating load balancer using ec2 instance created with private subnets. I have followed the exact method used in video. While creating load balancer, I have selected private subnet ec2-instances and under subnet tab I have selected both the public subnets. But still 0 of 2 instance in service gets showed.
And when I launch load balancer using public subnet ec2-instance and public subnet in subnet tab, I am successfully able to launch load balancer.
Could you please help me in that? And also why you used private subnet to create ec2-instance, when we had public subnet also with us??
Sir, I have one query, need help..
What does these 4 parameters indicate and the values with in them..(in ELB Configuration)
Timeout 5 seconds ??
Interval 8 seconds ??
Unhealthy threshold 2 ??
Healthy threshold 3 ??
Thank you in advance, i will wait for your response sir. Regards
Hi Anand,
For such small doubts, you can easily get it from the documentation.. That would save lot of your time.
@@knowledgeindia Yes agree.. got it..infact i could search the details after i had posted that query. I felt like to re-call the post :-). Thank you..
1) The instances what you have used server-1 and server-2, Can we ssh and connect?
2) The number of instances of LB are equal to number of AZs I configures right? If I use 4 AZs for LB, then 4 instances of LB will be running right?
1) they are private. you can via a Bastion host / jumpbox.
2) yes
Please support us by sharing our videos and channel on LinkedIn/FB/Twitter, to bring more such AWS videos.
Question and correcting my understanding time !!
----------------------------------------------------------------------
1. ELB cannot be attached to both public and private subnet at the same time, right? So the 1st line of defence [in fact after the sec group and ACL ] would be the public Subnet right? coz, typically in the private subnet, we would have hosted D.B or some critical application wherein we don't want any public to have direct access?
2. We can still have a separate ELB for private subnet traffics too?
3. If in case if we have only one ELB which is associated with the Public subnet, any flow to the private subnet from the public subnet will also be load balanced if we enable CROSS ZONE LOAD BALANCING?
4. And just to clear up certain terminologies, Do we really keep an ELB in public or private !! or do we associate the respective public and private instances with the ELB?
like always thank in advance :)
5. One subnet = one ACL, [Cannot be associated with more than one ACL ]
But one ACL can be assocated with multisubnets right ?
1. ELB cannot be attached to both public and private subnet at the same time, right? So the 1st line of defence [in fact after the sec group and ACL ] would be the public Subnet right? coz, typically in the private subnet, we would have hosted D.B or some critical application wherein we don't want any public to have direct access?
Ans: That is right. You make ELB either in Public or Private subnet and not both. Public ELB can be placed in front of Web-tier. Private ELB can be placed between Web-tier and App-tier.
2. We can still have a separate ELB for private subnet traffics too?
Ans: Yes
3. If in case if we have only one ELB which is associated with the Public subnet, any flow to the private subnet from the public subnet will also be load balanced if we enable CROSS ZONE LOAD BALANCING?
Ans: Cross zone load balancing has to deal with balancing of data between 2 AZs (irrespective of Public or private subnets). Additionally, only the instances registered to ELB would receive traffic via ELB.
4. And just to clear up certain terminologies, Do we really keep an ELB in public or private !! or do we associate the respective public and private instances with the ELB?
Ans: We first create ELB in Public or private subnets (based on the need) and then register the instances which need to receive traffic from that ELB.
like always thank in advance :)
5. One subnet = one ACL, [Cannot be associated with more than one ACL ]
But one ACL can be assocated with multisubnets right ?
Ans: It's NACL not ACL. Yes, one subnet can have only one NACL, but one NACL can be attached to multiple subnets. Some of these things are easily verifiable from console itself, while we do the practicals.
Keep learning.
Thanks a million sir !! Hail Knowledge India :)
while going through the steps to create the ELB, configure security settings in the ELB setup asks for the certificates. How can i address this? seems its a new feature
i guess the reason was being the HTTPS port option was selected. if only the HTTP alone is used. the issue would not be there.
thank you so much
I created two instances and attached to load balancer but i had a problem it shows instances r out of service
Thanks for this Vedio its really helpful ! one question thought, How those private instance were accessing internet as NAT is option is not enabled it seems in your demo route table ??
If private instance has to access internet, nat would be required. Please check our video - NAT & ELB difference ..
Now I understood. You have created VPC with CIDR range 10.0.0.0/24. So total 2 ^ (32-24) = 256 hosts available in this VPC. Among of them you want to assign 64 hosts as public sub-net so CIDR rang is /27 (32 hosts in each AZ). and 64 hosts in each private subnet ( total 128 hosts in private subnet. 2 AZ * 64 ). Please let me know whether my understanding is wrong or right.
please see carefully - 10.0.0.0/27 is for one public subnet which means one public subnet has 32 IPs, same for other public subnet.
Read my reply on other comment carefully and evaluate the IPs for all 4 subnets, you will understand.
yes. but you should not have edited the comment, rather written a reply .. anyway.. Please share the video & channel with your friends, if it helped you in learning..
After reading ELB doc not able to understand the difference in using listener 'TCP' and 'HTTP' and its use cases.
As explained in LIVE Session today, it affects the distribution mechanism.
TCP - simple round robin between instances
HTTP/HTTPS - instances which has least open requests, gets the next request.
Q: Can you come up with a use case to launch ELB using private address space
Thanks for the informative session, but the audio quality is not good for this particular video.
I try to explain in easy way. Thanks for appreciating it. Please support us by telling your friends about our videos. Thank you.
Can you please explain web tier and app tier?
good explanation. thanks. just 1 thing, the SG for the private instances could have be more locked down to only accept traffic from the public subnet, correct? thanks again.
Correct.. not from public subnet but from the Security group of elb.
KnowledgeIndia - AWS Tutorials Thank You!!
Good work, keep it going :)
Thanks. I hope you like other videos as well on AWS. Please SHARE and Subscribe.
If you liked the channel, please write a testimonial/recommendation here --- aws-tutorials.blogspot.in/p/do-you-like-it.html
I too appreciate with million of Thanks. My question is if we create production instance with private subnets than we don't get public ip address. how can we login the instance without public ip address?
Thanks Siva.
In such a case we use Bastion Host (or Jumpbox) in Public subnet. Jumpbox is just a simple small Windows/Linux machine in Public Subnet, so we first login to that Jumpbox; and then we can connect the instances in Private Subnet over the private IP.
Do not forget to SHARE the videos with your friends.
If you liked the channel, please write a testimonial/recommendation here --- aws-tutorials.blogspot.in/p/do-you-like-it.html
Sure I done it
Hi, what were the Inbound and OutBound rules for the security group associated with EC2 and Classic ELB, Can you please include them in the video and how did you create VPC, using Wizard?
Watch our networking playlist for VPC
@@knowledgeindia I know how to create Vpc I am just curious about inbound and outbound rules of the security groups used in the demo. Thanks
Very helpful information. Thank you! But when i try to browse the Public DNS/public IP in the browser am getting time out error like this (This site can’t be reached took too long to respond.) could you please explain, what could be the reason, Thank You.
Check the Security groups of ELB and EC2 instances. That could be blocking the traffic.
Please share the videos if you like it.
Thanks a lot, its working fine.
Quick question...There are lot of posts online which talk about need to open ephemeral ports for the ec2 instances else external clients won't be able to connect to our website. How come you have not defined / mentioned any ephemeral ports & yet you are able to access your website over internet? Thanks in advance
Neeraj,
Ephemeral ports will come into picture in case of NACL outbound rules. As the clients could be having different types of OS, typically all the Outbound rules are allowed in NACL. Hence, we don't need to do anything. Moreover, Security Groups are stateful and hence nothing to worry. Please see other videos, i have explained most of these things in detail.. Please don't forget to share with your friends all the videos you like.. Please recommend us on LinkedIn, write a Testimonial if you learned the concept and your questions are answered -- in.linkedin.com/in/knowledgeindia
Please help us to spread the knowledge to others as well; SUBSCRIBE to our RUclips Channel & LIKE and SHARE the videos if they helped you to learn.
We have many more videos on AWS topics, these are organized in playlists here -- ruclips.net/user/knowledgeindiaplaylists
You can subscribe to our blog to receive useful AWS related content -- aws-tutorials.blogspot.com
Thank you for the detailed explanation.
Did you first creat the webserver? for example an iis teste page?
You said to keep WebSeerver in Private subnet but in picture you have kept in Public. Why?
Please try to listen from 5:00 again. Webservers are in private only. In Public, i have shown internal instances of ELB.
I would request you to SUBSCRIBE our CHANNEL and look at our playlists for SA & SysOps here -- ruclips.net/video/ywHFXfuJoSU/видео.html &&& ruclips.net/video/UFSH-KuDGj8/видео.html
Connect with me on LinkedIn to read interesting important AWS updates --- www.linkedin.com/in/knowledgeindia
Please follow my FB page fb.me/AWStutorials & Twitter - twitter.com/#!/knowledge_india
And for AWS exercises, you can refer our blog -- aws-tutorials.blogspot.com/
Hi, Can someone clarify why do we have to create two separate web-servers?
What if we have a single web-server then can't we have scalability? As I thought if I attach websever to ELB then it will automatically scale up and down. Could someone please clarify this confusion?
The instances behind the load balancer would only scale if they are part of an auto scaling group.. watch our video on auto scaling
@@knowledgeindia Thank you for reply.
I have check auto-scaling video and my understanding + questions are written below.
1- In the current video is explaining the scenario when we are handling scalability oursleves.
2- For auto-scaling: Create an EC2 instance and install the software / application on it. I am not very sure if we can use this instance directly in Launch configuration or we must create an AMI. Would be helpful if you can clarify.
3- Launch a configuration that actually tells AWS what type of instances are required to be created in case of scale up operation.
4- Create Auto-scale group to define conditions when to scale up and down + what is min and max numbers of instances
Let me know if my understanding is correct.
Now I am wondering what if I need to modify my application ( enhancements / bug fixes etc ). What will be the steps to do it:
1- Create new AMI and then modify the existing configuration or launch a new one?
2- In case we must have to launch a new configuration then attach this one with the existing Auto-scaling group?
Answers here.
1.yes
2. you need to create AMI. because in Launch config, it asks you to select AMI.
3. yes.
4. term should be scale out and scale in. correct understanding.
1. yes. create a new launch config from the new AMI.
2. the update this launch config ID to the ASG.
I suggest you should do practical as well, so you will not have above doubts.. :)
Please share with your friends, if you like our videos..
@@knowledgeindia Thanks for replying. Now i have this basic understanding and image in my mind so time to move on to the practical.
I will for sure suggest your channel to my friends and colleagues.
Hi ,
If i deploy a firewall ,before the ELB. The ELB loadbalnces traffic in 2 AZ.
So incoming traffic (from internet goes from)
NAT->FIREWALL(Outside Interface) ->ELB-> AZ1 / AZ2
for outgoing traffic, the Server in AZ2 needs to reach the FIREWALL(inside) interface. How can we route the traffic from server in AZ2 to FW Inside interface?
You have few misconceptions as i observe from above statement. Please see other videos in playlist related to VPC, ELB, NAT etc. you will be able to understand.
sirji !! While i was working with the ELB's, I came across this scenario where I was able to add an instance [One instance ] to 2 ELB's . I found that little strange, hence reaching out to you to ask, if that behaviour was expected and can you help me with a live example.
Is it expected or not, is a different question..
But, technically this is possible. Think on a a machine there are 2 processes running (IIS on 80 and Tomcat on 8080). 2 ELBs could be sending traffic to these different processes.
ohh ..so when defining the load balancer, There is this listener configuration for load balancer and Instance protocol, So the INSTANCE PROTOCOL is the place where we can choose a different port for different services? right?
Yes. Right..
great content but the sound quality needs to be better. Please use a mic sir.
thanks .. you should find sound quality better in recent videos.
Hello Knowledge India,
I have deployed the nextcloud application in AWS. Below is the architecture
1) Created a VPC with 2 public and private subnet
2) Hosted nextcloud app in ubuntu in 2 EC2 instances in private subnet using a jump server(windows) in public subnet
3) Configured the RDS(Maria DB) to connect to NextCloud app
4) Created a Classic Load Balancer and configured 2 public subnets and added 2 running EC2 instances.
5) Created a proper security groups to access the application thro load balancer
Application is running fine and have checked the requests are going to both the servers.
Now I want to
1) Add both these Ubuntu servers into Auto Scaling group, so that when the user requests increases, few more EC2 instances boots up to handle the load.
2) To have lambda function to get db snapshot everyweek into S3.
Can you please help me
1. Create an auto scaling group (video is there) and then in that ASG, there will be an option to add already running instances to it.
2. See the video of lambda function . write a python script. in RDS, there would be createSnapshot action; use that & write it.
Hi sir,
Could you pls explain, the inbound and outbound rules Selected for the SG of this ELB. Because in video I could not find that info.
you can watch VPC video on our channel to learn that. go to vpc playlist.
Thanks, Question: While creating ELB, Can I use one Private and one Public subnet?
if so, then ELB will be public or private?
An ELB will always always have to be placed in a Public Subnet.
You cannot, or rather should not put an ELB inside a private Subnet.
REASON: The purpose of an Internet-Facing ELB is that it can forward traffic from Internet to all EC2 instances which are registered to it. And Private Subnets do not have Internet Gateways attached to it. Meaning they cannot recieve or send traffic to the internet(Unless they have a NAT attached to it). So when you put an Internet-Facing ELB in a private subnet, it will neither be able to recieve nor send traffic.
Did I answer your query ?
I have a doubt here sir. There are two subnets. Are subnets only ip addresses? Or We have instances in subnets?
As far as i can understand in the example there are two instances already mapped to the two subnets and apart from that te ELB internally launches two instances!
Can you please clarify on this! I took many examples can't understand!
#sastrite
SIr? Please!
I have completed the exact configuration ,jst as your guidance but my instance show out of service status in the ELB instance tab...pls reply me
Yes sir ! even mine also....@susan ! if you are done with the error will you please guide me?
Thanks sir. Sir can I have multiple instance type in single ELB Target group (1 Windows and 1 Linux)
yes you can keep.
Am not getting proper out put with same network architecture even I have opened port 80 in both security group of ec2 and Elb as well please help me
Please do again from scratch and make sure vpc is setup correctly. Check our vpc videos
@@knowledgeindia I have done all steps correct but I don't know why am not getting out put .
hi dear, i have a doubt, that is i have one instance is for only front end and another instance is for backend. and i want to add 2 backend instances into load balancer. how will i achieve this. please help me.
It would not be ideal to attach a backend and a front-end instance to same load balancer
@@knowledgeindia sorry, i want to attach 2 backend instances to load balancer. and not attaching front end instance to load balancer. front end is open to public but back end is not open for public. so in this case how i will achieve that.
Hi...I have one question. When we launch elb it will automatically launch ec2 instances? If yes, how many ?
No. Elb doesn't launch instances. That's the work of auto scaling group. Watch our video on auto scaling group
I have tried doing this but my both the instances failed health check up...could please help me in resolving this...like where I should check to pass the health check up
Please ensure what URL you are setting up in health check (e.g. index.php). Check if this URL is working on the instances?
I have not given url..just given their tcp port 80
Check Security group of your instances. and, see if the webserver is running on 80. If its Tomcat / Apache, it would be 8080.
I am using linux machine as a ec2 instance and also given user data same as given by you while creating instance. I tried to all the things same as done by you. Could you please help configuring SB for elb instance and for linuc ec2 instances. Might that would help me to pass the health check up for instances.
Is it essential that the instances need to be logged(SSHed) into first for them to pass health checks?
is there any requirement of NAT Gateway? I know that if my Instances are in private subnet and I want to access the internet from that private instances then NAT gateway is required. I am asking this question because my both private instances are out of service constantly and showing "instance has failed at least the UnhealthyThreshold number of health checks consecutively." error.
Please Help me.
Have your instances got the web server installed and the health check file is correctly placed? Also, review the security group to allow traffic from load balancer
@@knowledgeindia Everything was correct.Yesterday i used NAT gateway and everything was working. HOW???
how ELB's we can create in region?
you go to a region and then create ELB. You need to choose subnets in which you want to place it. i have shown the same in the video. An ELB can not span across regions.
Please share the videos. Also, i am starting an Online and Classroom training for people who want to move forward quickly..
Please see below for details, i am sure you will like it as you have liked my videos till now..
Details are given here ---
aws-tutorials.blogspot.in/2017/06/aws-solutions-architect-associate.html
aws-tutorials.blogspot.in/2017/06/aws-sysops-administrator-associate.html
Please let me know for any doubts you might have... :)
*Sorry Sir, but i am unable to create as in LOAD BALANCER , it is showing that the health checks are OUT OF SERVICE and according to this they are telling that my ec2 instance is not registered ?
Will you please help me to troubleshoot this!*
check your EC2 security groups .. and health related .html file.
yes sir ! i have checked them ...even I have used Bootstrap for HTML file
i think so there might be different problem as i am not able to create any of the load balancer now...
Though... thanku sir!
Hello Sir, Need one clarity, what is the SG rules (inbound) of your ELB in above example.
I tried all same but the instances are continuously showing out of service.
My Set Up :
2 Linux Instance in prv subnet that has apache web server running..
Both instance's have same SG that is configured to accept traffic over port 80 and 443 from "anywhere"
My query is what is inbound rule of ELB in public subnet.
Thank you
for ELB it should be 80 or 443 from anywhere.
for EC2, it should be 80 from ELB SG.
If instances are not showing healthy in Target Group, still go ahead & check by hitting Load Balancer URL.
@@knowledgeindia Thank you Sir. I will try this out.
Great Video!
I completed the setup as you have shown and shutdown both the instances which are in private subnets.
When I do the nslookup for the loadbalancer DNS. I see a public IP associated with it.
Is this the public IP of that instance which was created (internally) when loadbalancer was created?
Correct Anees.
Thanks. Do I need to remove the load balancer when not in use to avoid extra charges?
Yes, as you can see there is no so option. Also, always read about pricing of any service in documentation. It helps a lot. Don't forget to share the video :)
Yes, as you can see there is no so option. Also, always read about pricing of any service in documentation. It helps a lot. Don't forget to share the video :)
can we create ELB using free tier account?
If we add two instances in ELB (windows & linux) with web servers(IIS and apache) installed. As we will only use the DNS of ELB to access these services, how the ELB will know which service(IIS or APache) we are trying to access? because DNS address will always be the same.
Please see the Free tier video. Yes you can create ELB as part of free tier.
The service gets decided by the port you choose in Listener creation in ELB. Also, ideally you will keep same type of instances behind an ELB. E.g. all windows or all linux.
So, we have to use different ELBs for different applications?
Thanks a lot btw. Your videos are excellent.
Thanks a lot. On one machine you can have multiple applications available on different ports and configure the same in ELB.
Hello Sir, I tried to create the same but in ELB instances shows OutofService any suggestion
Look at your health check and instance security groups
@@knowledgeindia health is
Ping Target
HTTP:80/index.html
Timeout 5 seconds
Interval 30 seconds
Unhealthy threshold 2
Healthy threshold 3
security group of my private instances is allowing access from the security group of Load Balancer
nat gateway is set to allow internet access for private subnets in Private rout table
IGW is set for public for public subnets in main route table
I am not able to figure out where i am making a mistake
Thank you sir, now i am able to see instances inservice however i am unable to access the ELB dns in webpage, what could be the issue please suggest
hello KI, when i tried to configure the ELB with private instance the Instances are going out of Service what should i do?
help me out in this .
Please review the security group settings and the health check well. Try watching the video once again and follow the steps closely..
Thank you for your reply. Sir i have configured with the security group as shown in the video with port 80 and port 22 open to 0.0.0.0/0 still i am facing the same error. i have not configured the windows instance i have gone with Linux instance.
please let me know as what to do.
check if your application is running on 80. & you have necessary page (as specified in health check)
its running on both 80 and 22. my public instance is running healthy and it in Service, the private instance is showing OUT of Service even after so many rechecks.
@@vinayaka1154 ...if you have fixed it ...will you please help me?
Why launch ELB in public and not in private subnet?
It could be launched in Public or private. Depending on use case, we do it. Please read the documentation and do practical in parallel to understand well.
my instances in ELB is always showing OutofService.. plz let me know how I need to proceed.
please watch video closely once again and follow the steps. Check your health checks properly.
@@knowledgeindia ! I have gone through the video completely ..but not able to fix this...
@diya Hegde ....if you have fixed it will you please help me
@@saurabhkumarmodi4939 I think I can help you. I had a similar problem. Please let me know if you want help.
@@leensharma4203 ! yes sure, please!
@@saurabhkumarmodi4939 please tell me in detail about your running instances.
really liked the content but voice recording can be improved
Thanks for the videos.
Does WEBSERVER mandatory for ELB to work ?
I am trying to setup 1-ELB(classic) and 2-EC2 instances on the private subnet(same AZ). The EC2 instances have application running on IBM WebSphere.
App1 URL : ecserver1:9080/app-war-1.0-SNAPSHOT-websphere/ContextName/login.jsp
App2 URL : ecserver2:9080/app-war-1.0-SNAPSHOT-websphere/ContextName/login.jsp
I have created load balancer with requried SG [listener port open for 9080/80]. Pingpath set as "/app-war-1.0-SNAPSHOT-websphere/ContextName/login.jsp", http : 9080
When I am accessing LB URL - testelb:80/app-war-1.0-SNAPSHOT-websphere/ContextName/login.jsp am getting 503 error. Do I need to have WEB SERVER infront for ELB to work ?
register both instances to the ELB.
Thanks for the reply.
I should have mentioned that I have already registered the instances to ELB. Does ELB work with the WAS(application installed in IBM WAS 9.0 in this case)
Yes it should work.
Check the security group of EC2 instances. Make 9080 open in inbound. Also, see if health checks from ELB are successful and both instances are shown healthy in ELB.
both are healthy .. and ports are already added to sec group.
The issue was with NACL blocking the port. Thanks ..
Sir, please little loud your voice
Sure. Corrected in recent videos. Please check our channel
for those who have speed catch, proabably a good video. but for me i have to say sorry more than understanding, getting more confused. which are you clicking fast here and there man.
there is an option to run the video slowly, that might help..
content and explanation is awesome but sound quality and the way presenter is speaking is very bad
in recent videos, you should see some improvement .. check our latest videos.
Your voice is hardly understandable during demo. My suggestion is - when you are any throat problem, its better not to record, as it is not helping the audience. :)
Thanks for your suggestion