topic Re: multipathd can't remove paths in Operating System - Linux

multipathd can't remove paths

Matt Shaffer_1 — Wed, 05 May 2010 12:39:30 GMT

My OS is RHEL 4.6 and the kernel is 2.6.9-67.EL 32 bit. I can't remove multipaths to a disk that is no longer presented to the server. The disk does not show up when I run fdisk -l. Only multipathd is seeing it. I ran multipathd -k and removed the paths and map. When I run list paths I no longer see the paths. But then I get out of the menu, restart multipathd, and the paths and map for the phantom disk shows up again. This is driving me crazy.

Re: multipathd can't remove paths

Matti_Kurkela — Wed, 05 May 2010 13:00:30 GMT

Have you tried "multipath -F"?

Multipathd might be relying on the kernel's hotplug information, which is kept until the system is rebooted or the sysadmin explicitly removes it. This is required to handle smoothly a situation where a disk vanishes temporarily, then comes back.

Are the disk devices still visible if you run "ls /sys/block"? If so, use /sys/block//device/delete to tell the kernel that the device is gone and will not be coming back.

Example:
To tell the kernel that /dev/sdaa is gone for good:

multipath -F
echo 1 >/sys/block/sdaa/device/delete

MK

Re: multipathd can't remove paths

John Guster — Wed, 05 May 2010 14:20:53 GMT

after echo 1 to the delete file, reload with multipath -v3. your next multipath -ll should not have removed disks any more.

Re: multipathd can't remove paths

Matt Shaffer_1 — Wed, 05 May 2010 14:26:55 GMT

I had tried those steps but not in that order. So it kind of worked. I could delete the 4 paths but not the dm path. The paths are gone but the map is not.

mpath4 (3600508b4000755d60000d000000a0000)
[size=2 GB][features="0"][hwhandler="0"]
\_ round-robin 0 [enabled]
\_ #:#:#:# - 65:0 [failed][faulty]
\_ #:#:#:# - 65:48 [failed][faulty]
\_ round-robin 0 [enabled]
\_ #:#:#:# - 65:16 [failed][faulty]
\_ #:#:#:# - 65:32 [failed][faulty]

multipathd> list maps

mpath4 dm-8 [no scheduled failback]

[root@wshq-eod03 hbanyware]# echo 1 > /sys/block/dm-8/device/delete
-bash: /sys/block/dm-8/device/delete: No such file or directory

The result from multipath -ll is the same after running multipath -v3 also.

Re: multipathd can't remove paths

Matt Shaffer_1 — Wed, 05 May 2010 19:52:48 GMT

after doing all these steps and rebooting the paths are now gone. thanks all.

Re: multipathd can't remove paths

Matt Shaffer_1 — Wed, 05 May 2010 19:54:05 GMT

removing paths and rebooting solved issue.