multipath centos 5.4 (64bit ) + Dell md3000i

My kernel
2.6.18-164.el5

Before multipath

[root@my machine ~]# fdisk -l

Disk /dev/sda: 72.7 GB, 72746008576 bytes
255 heads, 63 sectors/track, 8844 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 104391 83 Linux
/dev/sda2 14 5657 45335430 8e Linux LVM
/dev/sda3 5658 8844 25599577+ 8e Linux LVM

Disk /dev/sdc: 1499.2 GB, 1499238236160 bytes
255 heads, 63 sectors/track, 182272 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdc doesn't contain a valid partition table

Disk /dev/sdb: 1499.2 GB, 1499238236160 bytes
255 heads, 63 sectors/track, 182272 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdb doesn't contain a valid partition table



Then edit the configuration file.

Mine /etc/multipath.conf

[root@my machine ~]# cat /etc/multipath.conf
defaults {
udev_dir /dev
user_friendly_names yes
max_fds 8192
}

blacklist {
devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
devnode "^hd[a-z]"
devnode "^sda"
devnode "^sda[0-9]"
device {
vendor DELL
product "PERC|Universal"
}
}



devices {
device {
vendor "DELL"
product "MD3000i"
product_blacklist "Universal Xport"
features "1 queue_if_no_path"
path_grouping_policy group_by_prio
prio_callout "/sbin/mpath_prio_rdac /dev/%n"
getuid_callout "/sbin/scsi_id -g -u -s /block/%n"
hardware_handler "1 rdac"
path_checker rdac
prio "rdac"
failback immediate
}
}

multipaths {
multipath {
device {
vendor DELL
product MD3000i
}
}
}


After this run

#multipath -F

#multipath -ll

[root@my machine ~]# multipath -ll
mpath0 (36001e4f000321e0800000ee74bbd2b12) dm-3 DELL,MD3000i
[size=1.4T][features=1 queue_if_no_path][hwhandler=1 rdac][rw]
\_ round-robin 0 [prio=200][active]
\_ 54:0:0:10 sdb 8:16 [active][ready]
\_ 53:0:0:10 sdc 8:32 [active][ready]
\_ round-robin 0 [prio=0][enabled]
\_ 51:0:0:10 sdd 8:48 [active][ghost]
\_ 52:0:0:10 sde 8:64 [active][ghost]

After multipath

[root@my machine ~]# fdisk -l

Disk /dev/sda: 72.7 GB, 72746008576 bytes
255 heads, 63 sectors/track, 8844 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 104391 83 Linux
/dev/sda2 14 5657 45335430 8e Linux LVM
/dev/sda3 5658 8844 25599577+ 8e Linux LVM

Disk /dev/sdc: 1499.2 GB, 1499238236160 bytes
255 heads, 63 sectors/track, 182272 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdc doesn't contain a valid partition table

Disk /dev/sdb: 1499.2 GB, 1499238236160 bytes
255 heads, 63 sectors/track, 182272 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdb doesn't contain a valid partition table

Disk /dev/dm-3: 1499.2 GB, 1499238236160 bytes
255 heads, 63 sectors/track, 182272 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/dm-3 doesn't contain a Valid partition table

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