Bug 2021216

Description of problem:
With logrotate 3.14.0 running in a container on the controllers, such as logrotate_crond in OpenStack 16.1, if a path in the logrotate configuration is a symbolic link that is not resolvable inside the container, logrotate exits normally but without finding any logs to rotate, even though there are potentially dozens of logs matching rotation criteria. 
This results in logs not being rotated and taking up many GB of space.

Version-Release number of selected component (if applicable):
logrotate 3.14.0

How reproducible:
Option #1 - How customers might encounter the issue
Install OpenStack 13 (logrotate 3.8.6). On the OpenStack controllers, the log directory /var/log/containers/swift will be a link to /var/log/swift. Inside the logrotate_crond container, that path does not resolve, but logrotate still works normally. But, after upgrading to OpenStack 16.1 (or presumably 16.2) which uses logrotate 3.14.0, logs will no longer be rotated.

Option #2 - To manually reproduce the issue
Install OpenStack 16.1 (logrotate 3.14.0). On the controllers, move the logs in the directory /var/log/containers/swift/* to /var/log/swift, then remove the /var/log/containers/swift directory and make it a symbolic link (ln -s /var/log/swift /var/log/containers/swift). The logs will stop rotating and running logrotate manually inside the logrotate_crond container will exit normally saying that there are no logs to process, even with -v, -d, and/or -f.

Steps to Reproduce:
Option #1 - How customers might encounter the issue
1. Install OpenStack 13.
2. Note that the controllers use a symbolic link from /var/log/containers/swift to /var/log/swift.
3. Note that there is a bind mount in the logrotate_crond container for /var/log/containers:/var/log/containers, but not a mount for /var/log (i.e. /var/log/swift exists on the host OS but not inside the container)
4. Upgrade to OpenStack 16.1.
5. Note that the symbolic link for /var/log/containers/swift -> /var/log/swift still exists.
6. Note that logrotate will stop rotating logs. Furthermore, '/usr/sbin/logrotate -v -f -s /var/lib/logrotate/logrotate-crond.status /etc/logrotate-crond.conf' run inside the container will exit with the message "No logs found. Rotation not needed." even though the logs require rotation.

Option #2 - To manually reproduce the issue
1. Install OpenStack 16.1.6
2. Note that the controllers use a directory for /var/log/containers/swift, not a link.
3. Note that logrotate run from within the container is working normally.
4. On the host OS (NOT inside the container), replace /var/log/containers/swift with a symbolic link to /var/log/swift
5. Run '/usr/sbin/logrotate -v -f -s /var/lib/logrotate/logrotate-crond.status /etc/logrotate-crond.conf' inside the logrotate_crond container. 
6. Note the message "No logs found. Rotation not needed." even though logs do require rotation.

Actual results:
The logrotate command inside the container exits with the message "No logs found. Rotation not needed." even though logs do require rotation.

Expected results:
Either logrotate needs to function even with an unresolvable symbolic link -OR- logrotate needs to give an error indicating that it can not proceed due to an unresolvable symbolic link. 

Additional info:
Option #1 above has been seen in a customer environment, but Option #2 will more readily allow for recreation of the problem, even though that isn't how customers will encounter the problem.