Chapter 9 Setting Up and Checking the device-mapper multipath
>
9.4 Recognizing the Post device-mapper multipath LUNs
9.4
Recognizing the Post device-mapper multipath LUNs
Check the device file created by the device-mapper multipath.
Also check that the device file is linked to the "/dev/dm-X" file.
Execution example
#cd /dev/disk/by-name/
#ls -l
lrwxrwxrwx 1 root root 10 Aug 25 13:40 mpatha -> ../../dm-0
lrwxrwxrwx 1 root root 10 Aug 25 13:40 mpathb -> ../../dm-1
lrwxrwxrwx 1 root root 10 Aug 25 13:39 mpathc -> ../../dm-2
lrwxrwxrwx 1 root root 10 Aug 25 13:39 mpathd -> ../../dm-3
lrwxrwxrwx 1 root root 10 Aug 25 13:40 mpathe -> ../../dm-4
lrwxrwxrwx 1 root root 10 Aug 25 13:39 mpathf -> ../../dm-5
lrwxrwxrwx 1 root root 10 Aug 25 13:39 mpathg -> ../../dm-6
9.5
Checking the device-mapper multipath Status
Check the path status using the "multipath -ll" command.
•
When both paths are in normal status (This example is for the ETERNUS2000)
The multipath consists of the block device names
"sde" and "sdc". "mpathc" is created.
# multipath -ll
mpathc (3600000e00d00000000000f7e00010000) dm-2 FUJITSU,E2000
size=10G features='1 queue_if_no_path' hwhandler='0' wp=rw
|-+- policy='round-robin 0' prio=150 status=active
| '- 4:0:0:1 sde 8:64 active ready running
'-+- policy='round-robin 0' prio=10 status=enabled
:
:
For SLES10, the following message may appear in the path status after executing the "multipath
-ll" command. However, there is no actual problem with multipath configuration and operation.
sde: Using deprecated prio_callout '/sbin/mpath_prio_alua %d' (controller setting)
sdc: Using deprecated prio_callout '/sbin/mpath_prio_alua %d' (controller setting)
P3AM-4152-02ENZ0
ETERNUS Disk storage systems Server Connection Guide (iSCSI) for Linux
(SUSE Linux Enterprise Server)
:
'- 3:0:0:1 sdc 8:32 active ready running
Two block device names are displayed
for a two-path configuration.
Please fixup /etc/multipath.conf
Please fixup /etc/multipath.conf
E2000 is displayed since the
ETERNUS2000 is connected.
When the path status is normal,
"active ready" is displayed.
23
Copyright 2010 FUJITSU LIMITED