Striped lvol's and mirroring

[Travis Harp_1]

I'm in the middle of migrating data from one EMC frame to another using lvm mirroring from the old devices to new ones on the new EMC frame.

On one of the vg's I'm getting this error:
Striped mirrors are not supported. To enable mirroring options (-m, -M, -c),
do not specify the striping options (-i, -I) when creating logical volumes.

From what I'm reading this means that the lvols are striped and I'm not going to be able to use the mirroring method to migrate this data.

If that is the case is there any work around to solve this issue?

Thanks,
Travis

[RAC_1]

man lvcreate. lvol, created with -i and -I options can not be mirroed with mirror disk software. But you can do that at storage level then.

[melvyn burnard]

On HP-UX 11.23 and below, striped mirrors are not supported. To be able to do this in 11.23, you would need to create the lvol using the Distributed option (-D) as per the man page (but I believe this is not true striped mirroring):
This example shows how the -D y option can be used to create EXTENT-BASED MIRRORED STRIPES.

Assume that volume group /dev/vgtest has two physical volume groups: pvg1, pvg2.

Assume that each physical volume group has 2 physical volumes.

Assume that the first physical volume in each pvg has 3 extents free and the second physical volume in each pvg has 2 extents free.
The following command creates a logical volume in vgtest with EXTENT-BASED MIRRORED STRIPES:

lvcreate -D y -s g -m 1 -l 5 /dev/vgtest

In HP-UX 11iV3 we now support striped mirrors

[Jarle Bjorgeengen]

"From what I'm reading this means that the lvols are striped and I'm not going to be able to use the mirroring method to migrate this data."

That is correct. You can't mirror lvols that is already striped.

I can't see how you can manage to do this without taking the filesystem(s) offline, unless you are able to use EMC tools diectly between arrays for the job (Like HP continous access for EVA and XP)

To shorten the offline period, if yoo do it from the host OS, you might want to :

1. Create new lvols on new storage. (with extent-based striping.)

2. Take a vxfs snapshot (requires advanced vxfs installed) of the existing filesystem(s)

3. rsync from the snapshot to the new filesystem

4. Stop applications writing to the filesystem

5. rsync the last bits of data from the existing filesystem(s)

6. Start the application on the new filesystem(s)

Rgds JarleB.