Alternate path to disks not working

[Coolmar]

Hi,

We have an HP 11.11 system attached to an IBM 8300 Shark SAN. The disks are recognized and working fine. When I do a vgdisplay the disks are there and the alternate path as well. When I tested the alternate path (unplugged the primary path FC cable) it did not fail over. So it seems that the alternate path is not working. It could be setup incorrectly by the SAN folks, but I have to exhaust all options on my end first. I just installed the IBMsdd (just to test if I need IBM software to make it work) but have no idea how to use it or what to do with it to set it up. If anyone can help, that would be great.

Thanks!

[Sundar_7 · Accepted solution]

Hi Sally,

HOw long did you wait for the PV to failover ? the default PV timeout is 60 secs. But if you have set it to any longer, then it will take longer for LVM to detect the PV failure and failover.

Can you post the output from the following commands ?

vgdisplay -v | grep dsk
dmesg | grep -i lvm

Sundar.

[Steven E. Protter]

Shalom,

do the alternate pathes show up on an IPL search command?

SEP

[Torsten.]

Try a "diskinfo" and "pvdisplay" to the alternate path. And wait up 90 s after you unplugged the cable. You also may try pvchange -s . You won't see the path in ISL>sea , because this is fibre channel. Don't worry.

[Coolmar]

Looks like I didn't wait long enough. It worked after a couple of minutes. Here is the dmesg output....

LVM: Performed a switch for Lun ID = 0 (pv = 0x00000000481e8000), from raw device 0x1f210100 (with priority: 0, and current flags: 0x0) to raw device 0x1f110100 (with priority: 1, and current flags: 0x0).
LVM: Performed a switch for Lun ID = 0 (pv = 0x00000000481e8000), from raw device 0x1f110100 (with priority: 1, and current flags: 0x0) to raw device 0x1f210100 (with priority: 0, and current flags: 0x0).
LVM: Performed a switch for Lun ID = 0 (pv = 0x00000000481de000), from raw device 0x1f210000 (with priority: 0, and current flags: 0x40) to raw device 0x1f110000 (with priority: 1, and current flags: 0x0).
LVM: Performed a switch for Lun ID = 0 (pv = 0x00000000481e8000), from raw device 0x1f210100 (with priority: 0, and current flags: 0x40) to raw device 0x1f110100 (with priority: 1, and current flags: 0x0).
LVM: VG 64 0x010000: PVLink 31 0x04c600 Failed! The PV is still accessible.
LVM: VG 64 0x010000: PVLink 31 0x04c500 Failed! The PV is still accessible.
LVM: VG 64 0x010000: PVLink 31 0x210000 Failed! The PV is still accessible.
LVM: VG 64 0x010000: PVLink 31 0x210100 Failed! The PV is still accessible.
LVM: VG 64 0x010000: PVLink 31 0x04c600 Recovered.
LVM: VG 64 0x010000: PVLink 31 0x04c500 Recovered.
LVM: Performed a switch for Lun ID = 0 (pv = 0x00000000481de000), from raw device 0x1f110000 (with priority: 1, and current flags: 0x0) to raw device 0x1f210000 (with priority: 0, and current flags: 0x80).
LVM: Performed a switch for Lun ID = 0 (pv = 0x00000000481e8000), from raw device 0x1f110100 (with priority: 1, and current flags: 0x0) to raw device 0x1f210100 (with priority: 0, and current flags: 0x80).
LVM: VG 64 0x010000: PVLink 31 0x210000 Recovered.
LVM: VG 64 0x010000: PVLink 31 0x210100 Recovered.