title: Problems connecting ssh to GCP's compute engine
body: <p>I paused and changed the cpu to improve the performance of the compute engine (ubuntu 18.04 ).</p>
  <p>However, after executing after setting, ssh connection is not possible at all in console, vs code.</p>
  <p>When ssh connection is attempted, the log of the gcp serial port is as follows.</p>
  <pre><code>May 25 02:07:52 nt-ddp-jpc GCEGuestAgent[1244]: 2021-05-25T02:07:52.4696Z GCEGuestAgent Info: Adding existing user root to google-sudoers group.
  May 25 02:07:52 nt-ddp-jpc GCEGuestAgent[1244]: 2021-05-25T02:07:52.4730Z GCEGuestAgent Error non_windows_accounts.go:152: gpasswd: /etc/group.1540: No space left on device# 012gpasswd: cannot lock /etc/group; try again later.#012.
  </code></pre>
  <p>Also, when I try ssh in vs code I get permission denied error.</p>
  <p>What is the exact cause and resolution of the problem?</p>
  <p>Thanks all the time for your help.</p>