cloud-init 0.7.9 fails for CentOS 7.4 in Cloudstack

[Ian Forde]

Environment:
CentOS 7.4, cloud-init-0.7.9-9.el7.centos.2.x86_64

Problem (quick):
CentOS 7.4 builds on Cloudstack 4.8 don't run cloud-init because the newer version of cloud-init doesn't appear to like the way the dhclient lease file is named.

Problem (long):

I've just built a CentOS 7.4 instance in one of my CloudStack 4.8 clusters. Unfortunately, cloud-init fails with the following in snippet in /var/log/cloud-init.log:

2017-09-13 18:53:00,118 - __init__.py[DEBUG]: Seeing if we can get any data from <class 'cloudinit.sources.DataSourceCloudStack.DataSourceCloudStack'>
2017-09-13 18:53:00,118 - DataSourceCloudStack.py[DEBUG]: Using /var/lib/dhclient lease directory
2017-09-13 18:53:00,118 - DataSourceCloudStack.py[DEBUG]: No lease file found, using default gateway

Where it then tries to use the default route to download userdata. The problem is that we're not using the Cloudstack VR as a default router, so I expected it to parse /var/lib/dhclient/dhclient--eth0.lease for the "dhcp-server-identifier" line.

Theory as to cause:
I believe that this change (https://github.com/cloud-init/cloud-init/commit/aee0edd93cb4d78b5e0d1aec71e977aabf31cdd0#diff-5bc9de2bb7889d66205845400c7cf99b) breaks cloud-init beyond the 7.3-distributed cloud-0.7.5 when 7.4 includes 0.7.9-9.

Fix:

Changing it from "dhclient." to "dhclient-" in /usr/lib/python2.7/site-packages/cloudinit/sources/DataSourceCloudStack.py on the running box with an installed RPM did the trick theoretically (after removing the pyc and pyo files, of course).

This *can* be patched around by RedHat/CentOS (and hopefully will), but I figure it might be better to take it straight upstream.

[Ryan McCabe (rmccabe)]

Please also create a red hat bugzilla for this, and I will make sure it gets pulled in when a fix is accepted here.

[Ian Forde (ianforde)]

Because $JOB has a RH support agreement, I created a support ticket (01932169). Do you also want a public bugzilla entry created? (Would require digging up my old RH Bugzilla creds...)

[James (james-redhat-bugs)]

This is a replicate of upstream bug
https://bugs.launchpad.net/cloud-init/+bug/1717147

As requested by customer in support case, I replicate this upstream bug to RHBZ.

Description of problem:

CentOS 7.4 builds on Cloudstack 4.8 don't run cloud-init because the newer version of cloud-init doesn't appear to like the way the dhclient lease file is named.

I've just built a CentOS 7.4 instance in one of my CloudStack 4.8 clusters. Unfortunately, cloud-init fails with the following in snippet in /var/log/cloud-init.log:

2017-09-13 18:53:00,118 - __init__.py[DEBUG]: Seeing if we can get any data from <class 'cloudinit.sources.DataSourceCloudStack.DataSourceCloudStack'>
2017-09-13 18:53:00,118 - DataSourceCloudStack.py[DEBUG]: Using /var/lib/dhclient lease directory
2017-09-13 18:53:00,118 - DataSourceCloudStack.py[DEBUG]: No lease file found, using default gateway

Where it then tries to use the default route to download userdata. The problem is that we're not using the Cloudstack VR as a default router, so I expected it to parse /var/lib/dhclient/dhclient--eth0.lease for the "dhcp-server-identifier" line.

Theory as to cause:
I believe that this change (https://github.com/cloud-init/cloud-init/commit/aee0edd93cb4d78b5e0d1aec71e977aabf31cdd0#diff-5bc9de2bb7889d66205845400c7cf99b) breaks cloud-init beyond the 7.3-distributed cloud-0.7.5 when 7.4 includes 0.7.9-9.

Changing it from "dhclient." to "dhclient-" in /usr/lib/python2.7/site-packages/cloudinit/sources/DataSourceCloudStack.py on the running box with an installed RPM did the trick theoretically (after removing the pyc and pyo files, of course).

This *can* be patched around by RedHat/CentOS (and hopefully will), but I figure it might be better to take it straight upstream.

Version-Release number of selected component (if applicable):
CentOS 7.4, cloud-init-0.7.9-9.el7.centos.2.x86_64

How reproducible:

Steps to Reproduce:
1.
2.
3.

Actual results:

Expected results:

Additional info:

[Scott Moser (smoser)]

Thanks for the good bug and root cause diagnosis.

I can see that the name of the files in /var/lib/dhclient on centos is in fact
 /var/lib/dhclient/dhclient--eth0.lease

the change clearly regressed reading those files.

More for information (not justification) /var/lib/dhclient/dhclient.eth0.leases.

Anyone here have an idea on why the '--' in that filename ? More just curious.

[James (james-redhat-bugs)]

Looks like a fix has been committed upstream, as noted in Launchpad at https://bugs.launchpad.net/cloud-init/+bug/1717147

Their fix is visible here: https://github.com/cloud-init/cloud-init/commit/da1db792b2721d94ef85df8c136e78012c49c6e5

[Scott Moser (smoser)]

This bug is believed to be fixed in cloud-init in 17.1. If this is still a problem for you, please make a comment and set the state back to New

Thank you.

[Ademar (ademar-redhat-bugs)]

The rebase is being tracked via Bug 1525267.

[errata-xmlrpc (errata-xmlrpc-redhat-bugs)]

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2019:2123

[James Falcon (falcojr)]

Tracked in Github Issues as https://github.com/canonical/cloud-init/issues/2998

[bugzilla (bugzilla-redhat-bugs)]

The needinfo request[s] on this closed bug have been removed as they have been unresolved for 500 days