Comment 43 for bug 1569925

@nacc: I can certainly do that - but it won't be quite as fast as my response yesterday, as the machine that exhibits this error is in use during the day, and I need to schedule the downtime.
In the meantime, I have installed a test machine from scratch, using the standard Ubuntu LTS server ISO. All I did on that machine was to set a static IP address, upgraded to the latest packages, and configured an open-iscsi mount.

Lo and behold, the test machine does not exhibit the error. My machine that does exhibit the error was upgraded using 'do-release-upgrade' from the previous LTS version (14.04). My Debian machines similarly were upgraded from wheezy to jessie (which introduced the issue with the switch to systemd).

So, for now, I would say there's something different between upgrade and fresh install that causes this. I will find some time today for the downtime of my other machine and attach the persistent journal info as requested.