How to tell how full the snapshot file system is?

[Dan Deck]

Does anyone know how to do this? We are using HPUX 11.11v1. I don't see any way of determining the usage of the snap file system mount.
BDF just mirrors what the parent fs is so no help there.

Any comments are appreciated.

Dan

[Mel Burslan]

By means of snap fs, if you are refrring to the volume that snapshots you are taking from your filesystems on a periodic (even in ad-hoc) basis for your SAN volumes, you will not be able to see them directly from HPUX. Since snap volumes or snap clones are a function og the SAN backend, you will need some sort of utility to dig up that information. And depending on the type of SAN backend you are using, such a utility might or might not be available to run on hpux.

In short, check with the vendor/maker of the SAN equipment to figure this out.

[Dan Deck]

This is indeed san disk, but it is using the HPUX snap file function in vxfs type file systems.

Thanks
Dan

[Mel Burslan]

Not a big fan of vxfs on hpux. Sorry. But I strongly suggest digging into vea to figure it out. Since I have never used OS based snaps before I am not sure how they are handled. But since this is a VX volumes function, your best bet is to look into vea. There has to be a way of telling it. I just don't know.

[VK2COT]

Hello,

I do not have any HP-UX 11.11 server to check
it at the moment, but this certainly works on
HP-UX 11.31 with LVM 2.2.

For volume groups 2.2 and higher, lvdisplay
can be used to display the characteristics
and status of snapshot logical volumes.

# lvdisplay /dev/vg01/lvol1
--- Logical volumes ---
LV Name /dev/vg01/lvol1
VG Name /dev/vg01
LV Permission read/write
LV Status available/syncd
Mirror copies 0
Consistency Recovery MWC
Schedule parallel
LV Size (Mbytes) 40
Current LE 10
Allocated PE 10
Stripes 0
Stripe Size (Kbytes) 0
Bad block NONE
Allocation strict
IO Timeout (Seconds) default
Number of Snapshots 3
Associated snapshots /dev/vg01/lvol1_S4
/dev/vg01/lvol1_S3
/dev/vg01/lvol1_S2

Then, one could check each snapshot:

# lvdisplay /dev/vg01/lvol1_S2
--- Logical volumes ---
LV Name /dev/vg01/lvol1_S2
VG Name /dev/vg01
LV Permission read-only
LV Status available/syncd, snapshot,space efficient
Snapshot Status operative
Mirror copies 0
Consistency Recovery MWC
Schedule parallel
LV Size (Mbytes) 400
Current LE 200
Allocated PE 30
Stripes 0
Stripe Size (Kbytes) 0
Bad block NONE
Allocation strict
IO Timeout (Seconds) default
Pre-allocated LE 170
Current pre-allocated LE 140
Unshared LE 30
Current pre-allocated PE 140
Original LV /dev/vg01/lvol1
Timestamp Wed Apr 28 14:01:14 2010
Auto Pre-allocation Enabled
Threshold Percent 70

Otherwise, isn't your snapshot mounted?
If so, you can check it with classical
commands (bdf and others). You can always mount your shapshot if needed...

Cheers,

VK2COT

[Dan Deck]

Unfortunately HPUX 11.11v1 does not display snapshot info using lvdisplay.

Thanks