snapd can't be purged with latest AWS Xenial AMI

[James McCoy]

The latest AMI for Xenial with the AMI name listed below fails when running apt-get purge snapd:
ubuntu/images/ubuntu-xenial-16.04-amd64-server-20190406

I have confirmed the command works as expected on the following AMI and older:
ubuntu/images/ubuntu-xenial-16.04-amd64-server-20190320

I have listed the output of the command below:

/home/ubuntu# apt-get purge snapd
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
  snapd* ubuntu-core-launcher*
0 upgraded, 0 newly installed, 2 to remove and 0 not upgraded.
After this operation, 94.8 MB disk space will be freed.
Do you want to continue? [Y/n] Y
(Reading database ... 51356 files and directories currently installed.)
Removing ubuntu-core-launcher (2.37.4ubuntu0.1) ...
Removing snapd (2.37.4ubuntu0.1) ...
Purging configuration files for snapd (2.37.4ubuntu0.1) ...
Stopping snap.amazon-ssm-agent.amazon-ssm-agent.service
Stopping unit snap.amazon-ssm-agent.amazon-ssm-agent.service
Waiting until unit snap.amazon-ssm-agent.amazon-ssm-agent.service is stopped [attempt 1]
snap.amazon-ssm-agent.amazon-ssm-agent.service is stopped.
Removing snap.amazon-ssm-agent.amazon-ssm-agent.service
Stopping snap-amazon\x2dssm\x2dagent-1068.mount
Stopping unit snap-amazon\x2dssm\x2dagent-1068.mount
Waiting until unit snap-amazon\x2dssm\x2dagent-1068.mount is stopped [attempt 1]
snap-amazon\x2dssm\x2dagent-1068.mount is stopped.
Removing snap amazon-ssm-agent and revision 1068
Removing snap-amazon\x2dssm\x2dagent-1068.mount
Stopping snap-core-6673.mount
Stopping unit snap-core-6673.mount
Waiting until unit snap-core-6673.mount is stopped [attempt 1]
snap-core-6673.mount is stopped.
Removing snap core and revision 6673
Removing snap-core-6673.mount
Final directory cleanup
Discarding preserved snap namespaces
Removing extra snap-confine apparmor rules
Removing snapd cache
rm: cannot remove '/var/cache/snapd/aux': Is a directory
dpkg: error processing package snapd (--purge):
 subprocess installed post-removal script returned error exit status 1
Processing triggers for man-db (2.7.5-1) ...
Processing triggers for mime-support (3.59ubuntu1) ...
Errors were encountered while processing:
 snapd
E: Sub-process /usr/bin/dpkg returned an error code (1)

[Michael Vogt (mvo)]

Thanks for the bugreport. This is fixed in xenial-proposed with snapd 2.38

[Robert C Jennings (rcj)]

Marking as 'invalid' cloud-images as this is not a issue particular to the cloud image build.

[Zygmunt Krynicki (zyga)]

The fix for the aux directory was released long ago. Marking as such.