change which primary path to use on a VG

[f. halili]

Hello everyone,

I have a VG and its disk have 3 ALTERNATE PATHS. See below. How can I change the primary path? I want to use c12t1d7 as the primary path not c9t1d7.

PV Name /dev/dsk/c9t1d7
PV Name /dev/dsk/c10t1d7 Alternate Link
PV Name /dev/dsk/c11t1d7 Alternate Link
PV Name /dev/dsk/c12t1d7 Alternate Link

Thanks,
f. halili

[Jeff_Traigle · Accepted solution]

pvchange -s /dev/dsk/c12t1d7

[Sandman!]

vgreduce all PVs above c12t1d7 until c12t1d7 cycles to the top of the list and then vgextend all the PVs that were above c12t1d7 in the beginning.

[Sandman!]

vgreduce all PVs above c12t1d7 until c12t1d7 cycles to the top of the list and then vgextend all the PVs that were above c12t1d7 in the beginning i.e.

# vgreduce /dev/vgname /dev/dsk/c9t1d7 /dev/dsk/c10t1d7 /dev/dsk/c11t1d7

# vgextend /dev/vgname /dev/dsk/c9t1d7 /dev/dsk/c10t1d7 /dev/dsk/c11t1d7

[Sandman!]

Sorry for double posts; Jeff's answer is perfect for what you are looking for.

[James R. Ferguson]

Hi:

In cases where you want to reorder a large number of pvlinks, (and can tolerate taking the volume group offline) you can 'vgexport' and 'vgimport' the volume group using the '-f outfile' to collect the pv_paths from the 'vgexport'; edit their order; and used the newly ordered members in the 'vgimport'.

See the manpages for 'vg(ex|im)port' for further details.

Regards!

...JRF...

[James R. Ferguson]

Hi (again):

To add to the use of 'pvchange'. You may want also to set 'pvchange -S' (n|y) to control whether or not LVM will switch back to the primary path that you originally had.

Too, using 'pvchange -s' will not be preserved across a reboot since the order of the pv_paths in the 'etc'lvmtab' is *not* affected. A primary path is simply one that occurs *first* in the list for a volume group in the 'lvmtab'.

Regards!

...JRF...

[f. halili]

thanks !