Volume full but Lun Online but not useable

[darraghos]

Hi guys. I had a funny issue a few days ago. We have the following:

• Volume with a single LUN in it both space guaranteed
• 2 snapshots in the volume
• 2 flexclones hanging off those snaps
• fractional reserve set to 0
• auto-grow disabled

Now, what happened was that the volume went to 100% but the LUN remained online. The OS saw that the disk had plenty of space on it and was trying to copy some large files onto it. The entire OS went into a hang because it couldn't commit the writes to the Storage. I would have assumed that the LUN would be brought offline in such a circumstances no?

[SeanHatfield]

Check lun show -v and see if someone turned on space_alloc.

[darraghos]

Thanks for taking the time to reply. I checked all LUNs and they all have:

• Space_alloc: disabled

Therefore I would have expected the LUN to go offline as per https://library.netapp.com/ecmdocs/ECMP1368845/html/GUID-AAA98EEC-0636-4EA8-96D4-FAFD95C94A29.html 

[Darkstar]

Have you ever found a solution for that issue? We have seen the same issue occur recently and we're equally baffled. Our config is very similar

[darraghos]

Never got an answer on this one from our vendor 😞

[liu]

Run the lun show -v command to check whether space-allocation is enabled

And modify it

Enable ONTAP space allocation for SAN protocols

What does the LUN option space_alloc do? - NetApp Knowledge Base

[Darkstar]

holy necropost, Batman!

You *do* realize that the post you replied to is almost 10 years old? It was on a 7-mode system so your links are not helping much. Also, Space Allocatiuon has already been suggested (and ruled out) as a reason a few posts earlier.