HPUX 11.0 : LVM Stripping Question

[LG Porter]

I recently inherited several L2000 Class servers. I am in the process of reviewing the LVM structure of the each logical volume configured. What is the best method for determining weather "stripping" was initially used when the logical volumes were created? When command is the best to used in order to identify if the logical volume or volume group is stripped?

[Pete Randall]

lvdisplay -v would show the extents spread across the different physical volumes.

Pete

[Jeff Schussele · Accepted solution]

Hi,

Use

lvdisplay /dev/vg_name/lv_name | grep -i stripe

If you get values OTHER than 0, then it's striped.

HTH,
Jeff

[Michael Steele_2]

You've got several considerations and two methods of stripping but here are the basic commands:

lvcreate -i 4 -I 64 -r N

-or-

lvcreate -D y -s g -r N

With the latter you stripe and mirror.

Use PVG's with both. Reason? I once had a 24 disk file system that ran out of space and needed another 24 disks before I could expand. We made the equivalent of a lun on a disk array.

HP recommends the PVG size at 4 disks. That way you can add PVG2 to PVG1, and then PVG3, etc., like bricks in a pyramid.

-I option, or stripe size has been recommended at 1 mb by EMC and 32 kb or 64 kb by HP XP. So investigate.

[S.K. Chan]

In one shot ..
# for lv in $(vgdisplay -v|sed 's/^[ \t]*//g'|grep -E 'LV Name'|awk '{print $3}')
> do
> echo "==$lv=="
> lvdisplay $lv|grep \^Stripes
> done

[Brian M Rawlings]

SK: excellent. Succinct, complete, and conclusive. Very nice.

M. Frederick Steele: HP does not support both mirroring and striping with LVM, only with VVM (Veritas volume manager, on HP-UX 11i only). So, even though it works, I wouldn't recommend it, since HP will shrug if there's a problem and say "well, we told you there might be issues with that..." I'd prefer to stay in a supportable mode, just in case.

Otherwise, this one has been nailed up good, I can't think of anything to add.

Later... --bmr

[Patrick Wallek]

Brian,

FYI, HP DOES support striping and mirroring with EXTENT-BASED stripes. See the '-D' option in the lvcreate man page.