Discovered we accidentally set a couple vols for SQL CVS clustered iSCSI LUNS to ‘all’ for tiering into fabric pool and StorageGrid.
We’ve changed this to ‘none’ now and are looking at running a ‘cloud-retrieval-policy promote’ against it to move the data back into the local performance tier.
My question is, will doing this incur a performance hit on the volume/lun, or cause the disk to temporarily be inaccessible like Bug 1425375, or when the composite aggregate tiering job is initially run against it?
#Cloud Tier Retrieval
neon peak
novel thistle
I've not seen a performance hit when doing the retrieval. No more so than the performance hit for reads and writes those SQLs would currently be experiencing.
Personally, I dont like the cloud retrieval promote function. I prefer to vol move the volume to another aggregate which will recall all the blocks.
neon peak
Understood, thanks for the reply
neon peak
Looks like there were about 100 vols impacted so not ideal to do vol moves for all of those. The promote feature looks like it worked.
When I checked status via ‘vol object-store tiering show it looks like everything completed. I imagined it would take some time to get back the data from storage grid, but maybe it was less data than we originally thought.
But will monitor and see if there are any more inaccessible events from the sql side
novel thistle
Nice work! Glad it looks all good, awesome. You can look at the "volume show-footprint" to see how much data has been tiered for each volume, if any. I usually use the -fields option and just grab the fields I want as the default show output isn't friendly for large lists of volumes.
For reference, in the list of fields, bin0 is the performance tier (so your ONTAP storage), and bin1 is the cloud tier (Grid),
wraith temple
Promote is slow and lazy compared to vol move on a single vol, but I can see why 100 volumes would be faster overall.
neon peak
I ended up using the cloud retrieval policy promote then object-store trigger.
Confirmed via vol show-footprint that everything now resides back on the performance tier!
Thanks again everyone!
novel thistle
Awesome outcome. Great work!