I am seeing a bunch of Snapshot Full warning events being generated recently from various volumes on our filers:
A Warning event at 22 Jun 10:03 Alaskan Daylight Time on Snapshot snapmirror_sql_trns_log.snapshot on Storage System netappfiler.contoso.com: The snapshot is 251.89% full (using 37.7 GB of 14.9 GB).
It might be that I am just tired but I am having a hard time really understanding what this means. My read of the documentation is that this Volume's snapshot reserve is completely full and the snapshots have spilled over into the unused space in the portion of the Volume that is allocated for normal use (How Snapshot copies and snapshot reserve use space in a volume).
I have a few questions about this condition:
- Is my understanding correct? I am a bit thrown by the terminology NetApp uses as well as the "snapshot is full" (does that mean one snapshot or the snapshot reserve)?
- What happens if the user data grows and competes with the snapshot spill space? Does the snapshot occupying it get deleted?
- What condition/s generally cause this to happen? It's my understanding that once the snapshot reserve is full or if a new snapshot will fill it, ONTAP just bumps the oldest snapshot/s out the reserve as necessary. In that case, how exactly can you even "fill the snapshot"?