metrocluster, can't create snapshot for mirror synchronization

carolinags — Thu, 05 Jun 2025 06:57:38 GMT

Hello,

I have installed a FAS3240 Metrocluster with DoT 8.0.1 7-mode two days ago, and the one thing that I cannot clear out is the following error:

MC3240B> Sat Mar 26 02:51:54 CET [Sat MarC3240B: raid.mirror.resync.snapcrtfail:warning]: Aggregate aggr0: could not create mirror resynchronization snapshot mirror_resync.0326015154(MC3240B) (No space left on device)

It comes on both nodes. They are configured equally, with one 64-bit aggregate containing vol0. The aggregate contains 14 disks with a raidgroup size of 14, the mirror has taken its 14 disks, and there are still 14 disks on each pool as spares. There is no data but vol0.

The error message should be quite straight-forward, no space. But it's empty. Then I see that there is no place for snapshots :

MC3240B> aggr show_space aggr0

Aggregate 'aggr0'

Total space WAFL reserve Snap reserve Usable space BSR NVLOG A-SIS Smtape

5136132096KB 513613208KB 0KB 4622518888KB 0KB 0KB 0KB

Space allocated to volumes in the aggregate

Volume Allocated Used Guarantee

vol0 349008156KB 6085340KB volume

Aggregate Allocated Used Avail

Total space 349008156KB 6085340KB 4273510132KB

Snap reserve 0KB 0KB 0KB

WAFL reserve 513613208KB 286900KB 513326308KB

MC3240B> aggr options aggr0

root, diskroot, nosnap=off, raidtype=raid_dp, raidsize=14,

ignore_inconsistent=off, snapmirrored=off, resyncsnaptime=60,

fs_size_fixed=off, snapshot_autodelete=on, lost_write_protect=on,

ha_policy=cfo

Can someone tell if this is the reason for the error? And is there a solution? I've been searching NOW up and down but apparently not well enough! Syslog translator gives me a fantastic : "there is no space on device".

Any help greatly appreciated! Thanks

Carolina

Re: metrocluster, can't create snapshot for mirror synchronization

sowens — Sat, 26 Mar 2011 13:42:29 GMT

The snap reserve on aggregate aggr0 is currently set to 0. As a result, the filer has no space allocated for the SyncMirror snapshot. Hence, we give the error of no space left on device.

The recommendation is to have the snap reserve for aggregates set to 5% in SyncMirror configuration. You can set the snap reserve by issuing the following

MC3240B> snap reserve -A aggr0 5

Re: metrocluster, can't create snapshot for mirror synchronization

carolinags — Sat, 26 Mar 2011 17:14:37 GMT

Thank you sowens!

That was what I was looking for. Since I couldn't find it, I was fearing that it was only at creation time that I could add the snap reserve.

It's working fine now.

Regards, Carolina

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metrocluster, can't create snapshot for mirror synchronization

Re: metrocluster, can't create snapshot for mirror synchronization

Re: metrocluster, can't create snapshot for mirror synchronization