I am relatively new to Historian administration and the system I am looking at now doesn't seem to be behaving as I would expect after reading the manuals.
This server has 7 archive files, ranging in age from 2015 to current, with the Primary archive having a start-time of 9/18/2017. This is not a big system, < 600 tags logged. The existing archive files are all Fixed size, 1024MB, with the exception of the Primary archive, which is (now) nearly 1500MB. It is also no longer Fixed, but AutoDyn.
As I understand it, with PI 2012 if no empty archive is available to shift into, the latest archive will be converted to AutoDyn and logging will continue until the disk is full. However, all archives are reported as shiftable, and the next shift is expected 27-Apr-2018, supposedly overwriting the oldest archive file. I am not sure if this will happen or not - My my reckoning this shift, if it were going to happen, should have happened when the current archive reached capacity, not after it had converted to AutoDyn.
The other thing that has me scratching my head, is that Auto Archive File Creation is enabled - a path is specified in the Archive_AutoArchiveFileRoot tuning parameter, along with Format and Extension parameters. There is more than sufficient free disk space (~100GB) for new archive files to be created before the existing archives are overwritten.
Could anyone shed some light on why the system is behaving in this way? I expect that the solution will involve manually creating a new archive and forcing a shift, but I would like some plausible explanation on how this scenario came to be.