I've think i've just hit a DataONTAP bug. Netapp 7.3.2 here. Snap list displays 0% everywhere, after several SMSAP(think SMO) snap restores from secondary (not Volume Restores but LUN restores directly in the FlexVol area), df reports this:
Filesystem total used avail capacity Mounted on
/vol/sap_XXX_sapdata/ 53GB 43GB 9GB 83% /vol/sap_XXX_sapdata/
/vol/sap_XXX_sapdata/.snapshot 0GB 19GB 0GB ---% /vol/sap_XXX_sapdata/.snapshot
LUN size is 15GB (really used is somehow ~9GB):
/vol/sap_XXX_sapdata/sapdata1/sapdata01.lun 15g (16106127360) (r/w, online, mapped)
snap list for volume:
Volume sap_XYZ_sapdata
working......
%/used %/total date name
---------- ---------- ------------ --------
0% ( 0%) 0% ( 0%) Feb 01 01:30 stor1(0151703761)_smsap_host1_XYZ_mirror_stor1_sap_XYZ_sapdata_1.18 (snapmirror)
0% ( 0%) 0% ( 0%) Feb 01 01:01 smsap_XYZ_host1_XYZ_f_h_1_f_h_1_8a4a65ed2ddfcee3012ddfceec8e0001_0
0% ( 0%) 0% ( 0%) Jan 31 17:01 smsap_XYZ_host1_XYZ_f_h_1_f_h_1_8a4a65ed2dde176a012dde1773ee0001_0 (snapvault)
0% ( 0%) 0% ( 0%) Jan 31 01:01 smsap_XYZ_host1_XYZ_f_h_1_f_h_1_8a4a65ed2ddaa881012ddaa88ad50001_0
snap delta for volume:
Volume sap_XYZ_sapdata
working...
From Snapshot To KB changed Time Rate (KB/hour)
--------------- -------------------- ----------- ------------ ---------------
stor1(0151703761)_smsap_host1_XYZ_mirror_stor1_sap_XYZ_sapdata_1.18 Active File System 10315488 0d 05:13 1974886.024
smsap_XYZ_host1_XYZ_f_h_1_8a4a65ed2ddfcee3012ddfceec8e0001_0 stor1(0151703761)_smsap_host1_XYZ_mirror_stor1_sap_XYZ_sapdata_1.18 15924 0d 00:28 33022.119
smsap_XYZ_host1_XYZ_f_h_1_8a4a65ed2dde176a012dde1773ee0001_0 smsap_XYZ_host1_XYZ_f_h_1_8a4a65ed2ddfcee3012ddfceec8e0001_0 339048 0d 07:59 42411.925
smsap_XYZ_host1_XYZ_f_h_1_8a4a65ed2ddaa881012ddaa88ad50001_0 smsap_XYZ_host1_XYZ_f_h_1_8a4a65ed2ddaa881012ddaa88ad50001_0 10389664 0d 16:00 649331.453
Summary...
From Snapshot To KB changed Time Rate (KB/hour)
--------------- -------------------- ----------- ------------ ---------------
smsap_XYZ_host1_XYZ_f_h_1_8a4a65ed2ddaa881012ddaa88ad50001_0 Active File System 21060124 1d 05:42 709088.452
If you take 10315488 kB and do math it is 9.837 GB since last snapshots (compared to AFS). The LUN size is 15GB, fractional_reserve=100%, LUN space reservation = enabled, snap reserve = 0%. There is 20.084 GB in snapshots, which is pretty close to what df .snapshot reports.
At least for me this is : LUN+LUN*fractional_reserve+space_used_by_snapshots= 15GB + 15GB + 20.084GB =~ 50 GB. Not sure how much of it is in fractional_reserver(BTW: how to check this?), i guess that at least: 19GB - (53GB - 43GB) = 19GB - 10GB = 9GB is in fractional_reserve, and this leaves me with 50GB-9GB = 41GB (pretty close value to the used space for Vol , as reported by df).
So why the hell snap list reports 0% everywhere? It looks like it doesn't support LUN snap restores "overwrite semantics"? Is this known "feature" ? In which version has this been patched?
-Jakub.
