Why is my VM instance stuck when I try to do SSH?

Question

When I build a VM default settings with Ubuntu 16 and CentOS 7 (those are the ones I've tried) I keep getting stuck when I try to do SSH. The message is:

Establishing connection to SSH server...

And then it times out with:

You cannot connect to the VM instance because of an unexpected error.
Wait a few moments and then try again. (#79)

I enabled OS login hoping the behavior will change but it just stays stuck.

Everything is default except that I enabled "HTTP and HTTPS" access when creating the VM. (I tried building it without these options checked and I get to the same problem.

Answer 1

Can you make sure that you have port 22 allowed from your network to the VM? You can create a rule by going to VPC --> Firewall Rules --> Create New Rule.

This page has detailed steps.

Hope this helps.

Answer 2

As manesioz commented, follow this guide to discard the common issues, as you said that this happens immediately after creation, most likely you're missing some firewall rules. Also consider to do a nmap scan to see if the port 22 is open in your instance. Do the next in cloud shell:

sudo apt-get install -y nmap

nmap -Pn YOUR_EXTERNAL_IP

Look for port 22 open