Application Load Balancers | How to create an internet facing load balancer in AWS?

This video explains how to setup an Application load balancer in AWS and load balance the data between servers behind private subnets.

start-up script:
#!/bin/bash
yum install httpd -y
systemctl enable httpd
systemctl start httpd

[jacqueskoorts]

I'm going to try this out now. What I like about this video is that its recent with the latest AWS console. Also it uses the ALB where other videos use the CLB. And lastly it explains why a public subnet is used in this video if mostly what this video is about is the private subnet. Well done!

[mathisart]

The explanation is such high quality and no-nonsense. This channel deserves more views.

[Vmr]

Hi there, I followed your video step by step and got both EC2 instances as failed helth checks. Here is what I did, I used the new console to setup a VPC of 2 public and 2 private subnets. The security group on the private subnets are:

Inbound:
1. ssh port 22 inbound from my IP
2. TCP 80 inbound from ALB security group

Outbound
1. Allow alltraffic outbound 0.0.0.0/0

ALB security group

Inbound
1. inbound allow all traffic 0..0.0.0/0

outbound:
1. outbound all all traffic 0.0.0.0/0
2. outbound TCP 80 to webserver 1 security group
3. outbound TCP 80 to webserver 2 security group

Health check status is as follows
Protocol HTTP
Port 80
Path /
Healthy Threshold: 5 consecutive health check successes
Unhealthy Threshold 2 consecutive health check fails
Timeout 5 seconds
Interval 30 seconds
success code :200

The NAT gateway is in public subnet 1
IGW is associated with the VPC

The route table associated with private subnet 1 has the following entries
1. 10.0.0.0/16 local
2. 0.0.0.0/0 Nat-gateway

The route table associated with private subnet 2 has the following entries
1. 10.0.0.0/16 local
2. 0.0.0.0/0 Nat gateway

The route table associated with the public subnet 1 has the following entries
1. 10.0.0.0/16 local
2. 0.0.0.0/0 internet gateway

The route table associated with the public subnet 2 has the following entries
1. 10.0.0.0/16
2. 0.0.0.0/0 internet gateway

ALB is associated with the two public subnets
ALB;s target group is the intsaces in the private subnet

I get both instances as unhealthy. Please could you help me? Thanks Happy to even share my WS account credentials for you to jump in and have a look.

[rolandoperez]

Excellent tutorial; you clearly explained the NAT and IGW components, as well as how to configure all routes 👍, Thank you; this tutorial has been greatly useful to me.

[MaHab]

Excellent and especially clear tutorial. A lot of thanks for instructor. This tutorial was very useful for me.

[valo]

This is the best video I’ve come across that does an excellent job explaining this topic. You’re amazing

[juliuscaeser]

wow! entire AWS ALB demystified in 15mins such that even my 12 yo can understand. Thank
you so much for explaining this in a simple and easy approach.

[mohitwasnik]

You just saved my motivation from assassination by frustration !!! 🐱‍👤 It was beautifully explained, cleared my doubts :)

[laurentsantiago]

Thank you very much for this excellent tutorial! It helped me a lot 👍

[tamilpattucassette]

Thanks for sharing this video. The concept has been covered but not with clear information's. say example - EC2 instance has created without adding tag, NAT gateway has not used too but it's created in this video.

[etza]

Yeah, is amazing tutorial, thank you very much!

[JohnSmithhh]

Thank you but in the begining of the video you're talking about private subnet but we doesn't link EC2 to them, so I'm a little bit lost. Why we create EC2 instance in public subnet?

[terrences]

This was a great explanation! So what could be the issue if the target group is reporting unhealthy instances. Thanx.

[RuznyAhamed-vx]

Great! I have a question, what if you created those four subnets within four different availability zones ? will it work?

[David-jfee]

You enabled load balancer in public subnet and registered target group in private subnets. Can you please explain this part

[malicksylla]

Have a question! Since we're not using the public subnet except for the ALB (and of course NAT Gw for EC2 in Private Subnets to get access to Internet...), I am wondering the need of the Internet GW? For me the IGW would be usefull if we need internet access for EC2 in public Sub... but in this case there is no EC2 in pub sub

[ivannadanielacevallos]

I am trying to access with putty to the instance to modify the HTML but it is not working, can you please help me I am working in the same IP address I specify in the Security Group.

[pranav]

Why you not used nacl here?
Videos are good

[jashwaaradhya]

Hi, i am running a simple php server on the ec2, not matter what i do, the load balancer health check always says unhealthy. I have the same setup as yours, but i am just running a index.php using apache2. Please help

[adinarayanareddy]

i have configured same way, but it's didn't workout. Servers are being unhealthy if we give public subnet while creating Load Balancer.