AWS EC2 IPv4 Public Address not reachable - amazon-web-services

I have deployed a Strapi.io app on AWS EC2 Following the documentation provided by strapi.io on their site.
Everything went great but when i try to reach the public IP of my EC2 instance, it is unreachable.
I have checked assigned an elastic ip.
I have also checked the gateway and security group, every thing is good but still my IP is unreachable.
Security Group Setting

Check your routing table of the subnet. If it routes the cidr 0.0.0.0/0 to the internet gateway, then the subnet is public and can connect by the public ip. If it routes to the NAT gateway, then the subnet is private and you need the load balancer or bastion to connect the ec2 on the private subnet by private ip. On the private subnet, the public ip is useless.

The issue here is that you need a web serever or reverse proxy like nginx, apache to listen on the port 80 and server your application. Currently, you would not have a web server configured for your app so you do not get any response when you hit the IP Address in your browser.

Related

How to route domain via openvpn cloud to aws internal load balancer?

am trying to route console.example.com to an internal load balancer that is located in a private subnet. My current architecture is as follows:
I have a public VPC and a private VPC.
A React app is running on an ECS cluster and its service (console-service) is located in the private VPC.
The internal load balancer has two listeners: one for HTTP on port 80, which forwards requests to port 443, and the other for HTTPS on port 443, which forwards requests to the task definition for the console-service. Additionally, the listener on port 443 has a certificate for console.example.com.
The OpenVPN connector's instance is located in the public VPC.
The public and private VPCs communicate with each other via a transit gateway.
I know that the routes are working because if I reach the console-service's private IP (private-ip:3000), I can access the website. I also know that the certificate and load balancer are working because if I SSH into an instance that is located in the private VPC and curl console.example.com, I can access the website. I believe that the issue is with the configuration of the OpenVPN's DNS settings. Currently, I added a network application that is like console.example.com - my-network, but I still cannot access the website with the domain.
I found out I made a rookie mistake. I just need to add HTTP/HTTPS to the security group's inbound rules that I use for my load-balancer.

auto assign public ip for ec2 webserver

I am going to deploy Nginx webserver to run my angular application in AWS ec2 and i have 2 subnets public and private. to reach my nginx web application I will use ALB which is in public subnet, now my question is
can i deploy the Nginx webserver(ec2) in private subnet.
in which case I should enable public IP to my nginx ec2 server
You should not assign a public IP address to the nginx EC2 server because:
It should only be accessed via the Load Balancer, and
It is in a private subnet, so the Public IP address will not work (that is, traffic will not be routed to the instance)
You should deploy the Load Balancer in the public subnet and the EC2 instance in the private subnet.
can i deploy the Nginx webserver(ec2) in private subnet.
Yes, you can. In ideal case the private webserver does not need any internet access.
in which case I should enable public IP to my nginx ec2 server
The server does not require public IP. If you place it in a private subnet, and you want your server to access internet (e.g. to install packages or updates) you have to setup NAT gateway in a public subnet.

Multiple EC2 instance in public subnet should have same IP address for outgoing traffic

I have an application hosted on an EC2 instance in public subnet. To integrate this app with a partner we need to whitelist public IP address of the EC2 instance on partner's firewall.
I want to configure auto-scaling of the application in such a way that outgoing traffic for my application's EC2 instances should be from same single IP address that only needs to be whitelisted on partner's end.
For a private subnet, I know that a NAT Gateway is a solution.
But for instances in a Public Subnet, how this can be achieved? any solution/suggestions will be highly appreciated.
All traffic from the instances will need to be redirected to send via a single resource, such as a proxy or a Gateway.
The simplest solution is as you stated -- configure the subnet to route all Internet-bound traffic to a NAT Gateway or a NAT Instance. All traffic from that instance will then come from a single IP address.
However, configuring the subnet in this way will mean that it is no longer a "public subnet", since a public subnet has Internet-bound traffic sent through an Internet Gateway rather than a NAT. So, it's actually the same as using a private subnet as you suggested in your question.
The only way to do it in a Public Subnet would be to specifically configure your apps to send requests via a proxy server, which would act in a similar way to a NAT Gateway/Instance.

Nginx Instances which are Launching in Public subnet with public IP in VPC but unable to connect to Network

Our AWS instances are created in a public subnet availability zone and are not able to connect to the internet and SSH. So all the resources are created on the public subnet and one AZ.
I have developed CF nginx template with single VPC and two public subnets, butsecond public subnet instances are unable to connect network and SSH even though I'm giving public IP of the instance in the browser it is not working.
The main issue is instances which are launching in the second public subnet are unable to connect internet system logs are:
Contact the upstream for the repository and get them to fix the
problem
Reconfigure the base URL/etc.
Disable the repository, so yum won't use it by default
Looking at the scenario generally in order to enable access to or from the Internet for instances in a VPC subnet, you must do the following:
Attach an Internet gateway to your VPC.
Ensure that your subnet's route table points to the Internet gateway.
Ensure that instances in your subnet have a globally unique IP
address (public IPv4 address, Elastic IP address, or IPv6 address).
Ensure that your network access control and security group rules
allow the relevant traffic to flow to and from your instance.
To use an Internet gateway, your subnet's route table must contain a route that directs Internet-bound traffic to the Internet gateway. You can scope the route to all destinations not explicitly known to the route table (0.0.0.0/0 for IPv4 or ::/0 for IPv6).
Kindly Refer this AWS Documentation and see what you are missing , as you must have skipped one of the above mentioned things.

The ec2 instance can't access internet in a public subnet without a elastic ip address?

I working on aws. I created a public subnet which has a network ACL allows all net traffic, and associated with a internet gateway in the route table.
And then I create a ec2 instance without elastic ip and a ec2 instance with elastic ip in it, and the security group also allows all traffic.
I ssh to the instance which has elastic ip. It works well when I run yum update and curl www.baidu.com and so on. But I can't access internet when I ssh to the ec2 instance which has no elastic ip. anyone knows that is why?
For accessing internet from EC2 instance in public subnet using Internet Gateway, the instance needs to have public IP address. Either one can configure the instance to have public IP address or attach EIP.
Reference: http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Internet_Gateway.html
If you do not want to attach public IP address for instances with Internet access (consider private subnets), NAT instance and NAT gateway can help.
Reference: http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/vpc-nat.html
As well as being in a subnet that has a route to an Internet gateway, an instance must have a public IP address to communicate with the outside world (this is distinct from an elastic IP).
You can specify this when launching an instance, if not there is a per subnet setting that controls this. The per subnet setting defaults to false other than default subnets in your default VPC. There are more details in the aws docs.
The problem lies with the gateway connected to the subnet you are using. To check the gateway you are using:
Go to the subnet you are using
Click on the Route table
Under Routes -> Destination look for 0.0.0.0/0 and check the gateway you have for it under Target
Here's how the gateways behave:
Internet Gateway (IGW) allows instances with public IPs to access the internet.
NAT Gateway (NGW) allows instances with no public IPs to access the internet.
This is a good article to help you understand and solve your problem:
https://medium.com/awesome-cloud/aws-vpc-difference-between-internet-gateway-and-nat-gateway-c9177e710af6