[LU-2337] Init scripts incorrectly detect '/dev/mapper' when importing pool

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.4.0
• Affects Version/s: Lustre 2.4.0
• Severity: 3
• Assignee: Prakash Surya (Inactive)
• Reporter: Prakash Surya (Inactive)

Description

If the /dev/mapper directory is present, but not used by ZFS, the init scripts will fail to import a zpool.

For example:

$ sudo /etc/init.d/lustre start
$ mount | grep lustre

The following patch fixes the issue for my unique case:

diff --git i/lustre/scripts/lustre w/lustre/scripts/lustre
index 55c6601..8c594ac 100644
--- i/lustre/scripts/lustre
+++ w/lustre/scripts/lustre
@@ -104,8 +104,6 @@ import_zpool ()
                args="$args -d $ZPOOL_IMPORT_DIR"
        elif [ -d "/dev/disk/by-vdev" ] ; then
                args="$args -d /dev/disk/by-vdev"
-       elif [ -d "/dev/mapper" ] ; then
-               args="$args -d /dev/mapper"
        fi
 
        if zpool status $pool >/dev/null 2>&1 ; then

$ sudo /etc/init.d/lustre start
Mounting lustre-oss/ost0 on /mnt/lustre/local/lustre-OST0000
$ mount | grep lustre
lustre-oss/ost0 on /mnt/lustre/local/lustre-OST0000 type lustre (rw)

But this is definitely not a correct fix, as it will break sites using multipath for ZFS pools.

My zpool uses the /dev/vdb device directly:

sudo zpool status
  pool: lustre-oss
 state: ONLINE
 scan: none requested
config:

        NAME        STATE     READ WRITE CKSUM
        lustre-oss  ONLINE       0     0     0
          vdb1      ONLINE       0     0     0

errors: No known data errors

And /dev/mapper contains entries for my root filesystem:

$ ls -l /dev/mapper
total 0
crw-rw---- 1 root root 10, 58 Nov 15 10:39 control
lrwxrwxrwx 1 root root      7 Nov 15 10:39 vg_toss-lv_root -> ../dm-0
lrwxrwxrwx 1 root root      7 Nov 15 10:39 vg_toss-lv_swap -> ../dm-1