EC2 - 'Failed to connect...' on newly created EC2 instance on specific AWS account

Hi,

I would start by confirming that e.g. network connection to public network is working correctly as well. We have a troubleshoothing guide that you can follow https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/TroubleshootingInstancesConnecting.html.

You can also do troubleshooting from the instance perspective by creating AWS Systems Manager VPC endpoints in the VPC. Then your instance would be able to connect to SSM without connection to public networks. https://docs.aws.amazon.com/systems-manager/latest/userguide/setup-create-vpc.html

Third option could be using VPC Reachability Analyser that enables you to specify start and end for your connection and it will tell if there is something blocking connection. https://docs.aws.amazon.com/vpc/latest/reachability/what-is-reachability-analyzer.html

Hi iBehr

Thanks for your comment - yep, done that.

The point is: I am not able to 'Connect' to newly created instance using the AWS Console on this specific account. There is a bug on this specific account regarding EC2 / SSH - using AWS Console (and SSH clients).

The one instance we have on this account is working fine, TCP-reachable - available through Internet, but not able to connect - nor SSH, nor AWS Console. But if a newly created EC2 is not 'connectable' no point in digging anymore on that specific instance.

This needs to escalate to respective AWS team, how and where can I log this case?

Thanks

Hi iBehr

Thanks for your comment - yep, done that.

The point is: I am not able to 'Connect' to newly created instance using the AWS Console on this specific account. There is a bug on this specific account regarding EC2 / SSH - using AWS Console (and SSH clients).

The one instance we have on this account is working fine, TCP-reachable - available through Internet, but not able to connect - nor SSH, nor AWS Console. But if a newly created EC2 is not 'connectable' no point in digging anymore on that specific instance.

This needs to escalate to respective AWS team, how and where can I log this case?

Thanks

Hi Riku and jose

Thanks for the suggestions but no joy. In reality the EC2 instance that we lost SSH access is still working fine (we only have one on this account), it has public HTTP access and is doing its job, I can stop/restart using AWS Console and all good, but I am not able to connect: nor SSH client nor AWS Console

Lets forget that instance and back to the basics - lets rephrase the question:

I am able to create a new EC2 instances on AWS Console, but not able to 'Connect' to that newly created instance using the AWS Console. And it only happens on this specific account, every other account I give support works just fine.

Where can I open an AWS Console bug ticket?

Have you checked the Network ACL (NACL) that is applied to the subnet in which the instance sits? Remember all that NACLs are not stateful and you must allow both the inbound and outbound flows.