2011-08-09 12:31 AM
Maybe I am missing something obvious but I don't understand this situation
We have a FlexVol of 3TB, Space Guarantee = None
The volume contains a single 1.5TB LUN, Space Reservation = None
The filesystem on the Lun (Linux) reports 81% used
However, when I check the stats of the volume the %Used is 80% but the Used Capacity is 1.41 TB
Why is the %Used value so high?
Solved! SEE THE SOLUTION
2011-08-09 10:53 PM
OK, so two possibilities
- Some space is reserved for snapshots (look at “df -r”)
- If volume is thin provisioned, “available” reflects free space in contained aggregate. What “df -Ah aggr-for-volrh2” says?
2011-08-09 11:05 PM
Doesn't look like space is reserved for snapshots. As I said, we don't use them at all
Filesystem kbytes used avail reserved Mounted on
/vol/volrh2/ 3221225472 1519112992 640049348 0 /vol/volrh2/
/vol/volrh2/.snapshot 0 0 0 0 /vol/volrh2/.snapshot
output of df -Ah is
Aggregate total used avail capacity
aggr1 8724GB 8114GB 610GB 93%
aggr1/.snapshot 459GB 226GB 232GB 49%
This is the output for Get-Navol for that aggregate
volrh1 online 819,2 GB 61% 317,8 GB False 109 32M aggr1
volrh2 online 3,0 TB 80% 610,3 GB False 109 32M aggr1
volwin1 online 1,4 TB 35% 923,4 GB False 109 32M aggr1
volwin2 online 4,5 TB 87% 590,1 GB False 116 32M aggr1
volrh2 and volwin2 are thin provisioned, the other two have a space guarantee of "volume".
volwin2 contains two 2TB "Space Reserved" luns so I guess that 590GB of free space is never going to be used by the volume.
Should I be worried now?
2011-08-09 11:23 PM
This explains why used + avail do not match total. As for why %used and Used do not match … well, I guess (total – avail)/total simply provides better approximation. Avail can be less than (total – used) under many conditions.
But to get definite answer you need to look at the sources after all ☺ In general I guess “avail” is the only thing that finally matters.