Location is unavailable error during acquisition

[glopesdev]

The below error was observed while collecting 24/7 data on AEON4.

The reason is currently unknown, but we speculated it could be either hard-disk failure, or a potential race condition with moving data to CEPH (although the latter is unlikely to cause folder deletion under normal conditions since new chunk files are always being written).

To investigate the first option we could run HDD tests on the M2 drive in AEON4 which is already potentially a couple of years old.