How to stripe a raw lvol - not mirrored

[Torsten.]

The lvextend stuff:

lvextend -L 8192 /dev/vg_ora/lvol1

[Torsten.]

The man page tell you a correct formula for a correct stripe size, but it doesn't know what is the best size for you ... ;-))

[Ganesan R]

Hi All,

There are two types of striping available on HP-UX. One is Block based striping. For Block based striping you need to specify the no of slices/disks by using -i and the stripe size using -I along with -C. Use lvcreate and lvextend commands to create Block based striping. But note that Block based striping is not supported in conjunction with LVM mirroring.

The other one is extend based striping popularly known as Distributed allocation policy. It is supported with LVM mirroring. If you need to mirror then you also need to create physical volume groups(PVG). Use -D option to create extend based striping.

Hope this helps.

[Patrick Wallek]

I see no reason to do your lvcreate and lvextend separately. You get no real benefit of doing them separately.

lvcreate -L 8192 -n lvol1 -r N -i 4 -l 128 /dev/vg_ora

(I forgot to put the '-L' in my earlier lvcreate).


The stripe size is entirely up to you and whatever is best for your environment. This is where testing before putting things into production comes into play.

[Ganesan R]

I explain why we need to use lvcreate first then lvextend.

If you use lvcreate directly it will create the LV on first available disks on that VG.

Whereas if you want to create the LV on specific disks, then you will have to create the LV with 0 size using lvcreate and then extend it on specific disks by using lvextend.

[ConnieK]

I thank all of you for your valuable input. Patrick had the first correct answer, I was looking for the -i and -I flags. Even though there was another question raised about the stripe size, which I don't think can be thoroughly answered other than "It depends on your environment", I was successful in creating all the raw volumes I needed. I am not sure that they are perfect in every way (meaning stripe size, distribution and efficiency), but at least they are done.