Accidentally (I think) disabled VM ingress tcp22/SSH firewall rule.

[MikaelBKR]

I cannot establish a SSH connection to my VM, every time I try I get code 4003 (Reason: failed to connect to backend). I think I may have accidentally UFW reset the firewall internally? Regardless, what can I do to fix this? Image attached

[DamianS]

Hello @MikaelBKR ,

Welcome to the Google Cloud Community. Screenshot indicates that you don't have FW rule for IAP SSH connection. Simply follow this [1].tutorial, and you should be able to connect via SSH.

[1]. https://cloud.google.com/iap/docs/using-tcp-forwarding

cheers,
DamianS

[lawrencenelson]

Greetings @MikaelBKR,

Welcome to the Google Cloud Community!

The Error code 4003 means that [1]:

This might mean the instance isn't listening on the port you're trying to connect to or the firewall is closed. Either of those issues could also cause the start-up connectivity test to the VM instance to fail.

Ensure that the listening process on the VM is running and listening on the correct port. Also, verify that your Google Cloud firewall is configured correctly and open on the port you're connecting to.

You may view this document on how to create a firewall rule - Create a firewall rule.

[1]. https://cloud.google.com/iap/docs/faq#error_codes