topic Re: Replacing SAN switch in Operating System - HP-UX

Replacing SAN switch

john D_3 — Tue, 06 Aug 2013 13:19:09 GMT

Storage team is planning to replace existing SAN switch with DCX switch. HP UX 11.11 and 11.23 servers are connected. There will be no change on Storage array level. All HP UX machines are connected with two paths. They will move first path and after few mintues second one. Does this change the device files? What are the precautions

Thanks

Re: Replacing SAN switch

Torsten. — Thu, 08 Aug 2013 04:45:31 GMT

Do the change online or offline (from hp-ux point of view).

The h/w path will change, so all LUNs will get new device files!

offline:

vgexport all the LUNs, install the new switches and do vgimport

online:

switch off one path, add the new path to each VG, then do the same on the other SAN. Finally remove the old path from the vg

Re: Replacing SAN switch

P Arumugavel — Wed, 07 Aug 2013 19:43:08 GMT

Be cautious when you remove the paths from the VG.

Rgds...

Re: Replacing SAN switch

ayseif — Fri, 30 May 2014 03:41:10 GMT

sorry, if i have same problem. but we already migrate 2 path go to new switch. now my vg not activated.

vgdisplay: Cannot display volume group "/dev/vgeva01".
vgdisplay: Volume group not activated.

Re: Replacing SAN switch

Bill Hassell — Mon, 02 Jun 2014 12:14:15 GMT

>> now my vg not activated.

What did you do before moving the connections?

You should have run vgexport with the -s and -m options to create a mapfile.

If you did not do anything, moving the connections has removed all the disk LUNs. You'll see this when you type vgdisplay.

Since the device files have changed, you'll need to run these commands:

umask 022
vgexport -m /etc/lvmconf/vgeva01.mapfile -s vgeva01
ioscan -fC disk
insf -C disk
mkdir /dev/vgeva01
mknod /dev/vgeva01/group c 64 0x100000
vgimport -m /etc/lvmconf/vgeva01.mapfile -s vgeva01
vgchange -a y vgeva01

Now all the above assumes there are no additional error messages and that the group file 0x100000 is a unique value. Be sure to copy all the messages on the screen if something doesn't work.