using tramp over aws ssm proxycommand

Question

I'm trying to get tramp to use my ProxyCommand from my ~/.ssh/config (pasted below), specifically for AWS SSM. Should I expect this ProxyCommand to work, maybe something is wrong with my environment or how I'm invoking tramp? Or would tramp need changes to its source to support AWS SSM?

I try C-x C-f /ssh:i-8746484eadb75:/var/log and it asks me if I want to create the directory or file y/n - never seems to even try connecting to the remote host or looking at my ~/.ssh/config and ProxyCommand.

Any pointers or direction would be most welcome, TIA!

Host i-* mi-*
     ProxyCommand sh -c "aws ssm start-session --target %h --document-name AWS-StartSSHSession --parameters 'portNumber=%p'"
     User ec2-user

I'm using emacs 26.3 (9.0) on osx catalina 10.15.3.

Answer 1

Using the temporary test AWS account, I have been able to access that file system via Tramp. Necessary configs are

1. If you use another AWS profile but default, you shall tell it to Emacs. Add to your ~/.emacs

   (setenv "AWS_PROFILE" "my_profile")
   

2. Add your private key file to ~/.ssh/config

   Host i-* mi-*
        ProxyCommand sh -c "aws ssm start-session --target %h --document-name AWStartSSHSession --parameters 'portNumber=%p'"
        User ec2-user
        StrictHostKeyChecking no
        IdentityFile ~/.ssh/id_rsa_aws