2009-11-01 06:39 AM
Can pls help me interprete the available space?
n3300> aggr show_space -h
Total space WAFL reserve Snap reserve Usable space BSR NVLOG
4138GB 413GB 186GB 3538GB 0KB
Space allocated to volumes in the aggregate
Volume Allocated Used Guarantee
vol0 873GB 202GB volume
vol2 252GB 106GB volume
Aggregate Allocated Used Avail
Total space 1126GB 309GB 2615GB
Snap reserve 186GB 40MB 186GB
WAFL reserve 413GB 42MB 413GB
n3300> lun show
/vol/vol0/qtvms1a/lun0 60g (64424509440) (r/w, online, mapped)
/vol/vol0/qtvms4a/lun0 180g (193273528320) (r/w, online, mapped)
/vol/vol0/qtvms5a/lun0 60g (64424509440) (r/w, online, mapped)
n3300> df -h
Filesystem total used avail capacity Mounted on
/vol/vol0/ 671GB 495GB 176GB 74% /vol/vol0/
/vol/vol0/.snapshot 0KB 4324KB 0KB ---% /vol/vol0/.snapshot
/vol/vol2/ 250GB 249GB 486MB 100% /vol/vol2/
/vol/vol2/.snapshot 0MB 0MB 0MB ---% /vol/vol2/.snapshot
1. Aggr0 has total space of 3.5TB. Correct?
2. How much space is available in vol0? I think it should be around 600GB, but why the df -h command shows only around 176GB?
Solved! SEE THE SOLUTION
2009-11-01 11:51 AM
Well, some ideas
2009-11-01 01:50 PM
This is the lun status -b:
n3300> vol status -b
Volume Block Size (bytes) Vol Size (blocks) FS Size (blocks)
------ ------------------ ------------------ ----------------
vol0 4096 176060424 176060424
vol1 4096 471859200 471859200
vol2 4096 65536000 65536000
Yes, lun reservation is enabled.
So, can I still create lun on vol0 for about 300GB? I'm not sure what "else" is 200GB.
2009-11-01 05:17 PM
1. You have put LUNs in the same volume as the system files, vol0. It is NetApp best practice and industry standard to NOT mix vol0 with any LUNs or other way of serving
2. You could easily reclaim some space by turning snap reserve to 0 (zero) on your aggregate and having no snapshots at aggr. level. Unless you ever think you will overwrite your entire
aggregate there is no need for this space to be reserved. I d recommend turning snapshots off and having no snap reserve, but its your call. You might have the option to use it.
2009-11-01 10:37 PM
He has volume of size 671G (as confirmed by vol status -b). How comes that aggr show_space shows that 873G are allocated for this volume? What consumes extra 202G? How is it related to either system volume or aggregate snap reserve?
2009-11-02 12:15 AM
Can you give us the "df -hr" output, which will show us the space used by the fractional reserve.
My guess is that the vol size shown by "df -h" + fractional reserve space = volume allocation in "aggr show_space". Your "df -gA" will also show a used that will be less than total space allocated as shown in "aggr show_space". Why NetApp does it this way, I don't know
2009-11-02 12:25 AM
n3300> df -hr
Filesystem total used avail reserved Mounted on
/vol/vol0/ 671GB 590GB 81GB 199GB /vol/vol0/
/vol/vol0/.snapshot 0KB 4324KB 0KB 0KB /vol/vol0/.snapshot
/vol/vol1/ 1800GB 1800GB 0GB 0GB /vol/vol1/
/vol/vol1/.snapshot 0TB 0TB 0TB 0TB /vol/vol1/.snapshot
/vol/vol2/ 250GB 249GB 486MB 0MB /vol/vol2/
/vol/vol2/.snapshot 0TB 0TB 0TB 0TB /vol/vol2/.snapshot
n3300> df -gA
Aggregate total used avail capacity
aggr0 3538GB 922GB 2615GB 26%
aggr0/.snapshot 186GB 0GB 186GB 0%
aggr1 3538GB 1802GB 1736GB 51%
aggr1/.snapshot 186GB 39GB 146GB 21%
Thanks for helping me. I'm really newbie here.
2009-11-02 12:36 AM
Hmm ... question: does NetApp reserve space immediately or only when snapshot is created? I remember having read something on this matter but forgot where.
If space is reserved immediately, df output makes sense. aggr show_space still not
OK, answering to myself. Quoting TR-3483: Data ONTAP removes or reserves this space from the volume as soon as the first Snapshot copy is created. There are some snapshots on vol0 (as indicated by snap reserve being != 0), which explains reservation.
Does not explain aggr show_space though
Message was edited by: aborzenkov
2009-11-02 01:14 AM
Nice, we found the missing 200 GB in the fractional reserve space. And yes, I also don't understand why NetApp did it this way
Assuming vol0 is the root volume, don't put LUNs in your root volume because it is not supported.
2009-11-02 01:29 AM
Ok, I've made mistake by using vol0 for LUN.
Can pls tell me the primary reason why I shouldn't do that?
Any remediation I can do about it? Maybe moving the LUN to other volume. Is it risky?
So, for this mistake, how much space I've wasted? Is it the 200GB?