Comment 1 for bug 1938299

[Summary]
I believe this problem is related to a change in behavior in cloud-init version 21.2-43-g184c836a-0ubuntu1 due to comparing two different daily impish images before and after this update.

The problem appears in a gcp account which currently has multple global sshkeys associated with different users. For example, we have keys for a 'testuser' and 'testuser2' account. When booting the older serial (as well as older releases), we see accounts created for 'testuser', 'testuser2' and 'ubuntu'. For the newer serial, we only see an account for 'ubuntu'. As our test automation uses one of the 'testuser' keys, it can no longer access impish VMs.

I've included the package list below from my two test systems. Including the google-agent packages since these could also be suspect.

[Expected behavoir]
If I have a gcp account with global ssh keys associated with non-ubuntu users, I expect those users to be present in the VM after launch and .ssh/authorized_keys updated with those public keys.

[Current behavoir]
Only the 'ubuntu' user is being created

[Package list with unexpected behavior - impish 20210728 serial]
$ dpkg -l|grep cloud-init
ii cloud-init 21.2-43-g184c836a-0ubuntu1 all initialization and customization tool for cloud instances
ii cloud-initramfs-copymods 0.47ubuntu1 all copy initramfs modules into root filesystem for later use
ii cloud-initramfs-dyn-netconf 0.47ubuntu1 all write a network interface file in /run for BOOTIF
$ dpkg -l |grep agent
ii google-guest-agent 20210414.00-0ubuntu1 amd64 Google Compute Engine Guest Agent
ii google-osconfig-agent 20210219.00-0ubuntu1 amd64 Google OS Config Agent
ii gpg-agent 2.2.20-1ubuntu4 amd64 GNU privacy guard - cryptographic agent
ii libpolkit-agent-1-0:amd64 0.105-31 amd64 PolicyKit Authentication Agent API
ii lxd-agent-loader 0.4 all LXD - VM agent loader

[Package list with expected behavior - impish 20190719 serial]
$ dpkg -l|grep cloud-init
ii cloud-init 21.2-3-g899bfaa9-0ubuntu2 all initialization and customization tool for cloud instances
ii cloud-initramfs-copymods 0.47ubuntu1 all copy initramfs modules into root filesystem for later use
ii cloud-initramfs-dyn-netconf 0.47ubuntu1 all write a network interface file in /run for BOOTIF
$ dpkg -l |grep agent
ii google-guest-agent 20210414.00-0ubuntu1 amd64 Google Compute Engine Guest Agent
ii google-osconfig-agent 20210219.00-0ubuntu1 amd64 Google OS Config Agent
ii gpg-agent 2.2.20-1ubuntu4 amd64 GNU privacy guard - cryptographic agent
ii libpolkit-agent-1-0:amd64 0.105-31 amd64 PolicyKit Authentication Agent API
ii lxd-agent-loader 0.4 all LXD - VM agent loader