Why was this role included in common.yml?

[accelas]

Given both debian and ubuntu are now running with journald by default. It seems after running common.yml, journald and rsyslog are running side-by-side.

[drybjed]

Good question! The rsyslog service is installed by default on Debian Wheezy, Jessie, Ubuntu systems as well. I wasn't able to test this on Debian Stretch at the moment.

The rsyslog in Jessie was installed by default to provide persistent, cleartext logs. The journald logs are not persistent by default and it has/had issues where the persistent logs in /var/log/journal/ directory could get corrupted and break the logging altogether. Cleartext logs allowed easier transition from older systems to Jessie which shipped with systemd for the first time.

The journald in Debian Jessie doesn't support remote logging. The rsyslog service can be used as a replacement to forward logs to a different system. However, it looks like in Stretch, systemd-journal-remote will be available so it can take over. It is available in jessie-backports as well, but that requires upgrade of the systemd package to version from jessie-backports.

So, why is debops.rsyslog by default in the common.yml playbook? It was there from the very beginning. The initial role didn't do much, just redirected cron messages to a separate file so that they wouldn't spam /var/log/auth.log. This was the status quo for a long time, until the role was revisited and expanted to manage rsyslog service properly. The reason for staying in the common.yml playbook is that this way the syslog configuration can be sorted out early on and logs could be redirected to different files or hosts almost from the start.

I suppose that with systemd-journal-remote coming up the debops.rsyslog role could be removed from the common.yml playbook. It can still be enabled farily easily via an Ansible inventory group if someone needs it. The rsyslog service still will be installed by default by Debian Installer though. Right now there's no good way to automatically purge it by DebOps after journald is configured, but a role for that could be written, say debops.apt_purge which would purge unwanted packages early on.