REDHAT DEVICE MAPPER MULTIPATH
1) DM Software Installation
yum install device-mapper-multipath
2) Initialize /etc/multipath.conf file
mpathconf --enable
3) Start multipath service
service multipathd start
4) If you do not want to use user friendly name
mpathconf --enable --user_friendly_names n
5) Ignoring Local Disks when generating Multipath devices
multipath -v2 (shows local disk, /dev/sda, in the multipath map)
create:
SIBM-ESXSST336732LC____F3ET0EP0Q000072428BX1 undef WINSYS,SF2372 size=33 GB features="0" hwhandler="0" wp=undef `-+- policy='round-robin 0' prio=1 status=undef
- 0:0:0:0 sda 8:0 [---------
device-mapper ioctl cmd 9 failed: Invalid argument device-mapper ioctl cmd 14 failed: No such device or address
create: 3600a0b80001327d80000006d43621677 undef WINSYS,SF2372 size=12G features='0' hwhandler='0' wp=undef `-+- policy='round-robin 0' prio=1 status=undef
- 2:0:0:0 sdb 8:16 undef ready running `- 3:0:0:0 sdf 8:80 undef ready running
create: 3600a0b80001327510000009a436215ec undef WINSYS,SF2372 size=12G features='0' hwhandler='0' wp=undef `-+- policy='round-robin 0' prio=1 status=undef
- 2:0:0:1 sdc 8:32 undef ready running `- 3:0:0:1 sdg 8:96 undef ready running
In order to prevent the device mapper from mapping
/dev/sda in its multipath maps, edit blacklist section in
/etc/multipath.conf
blacklist {
wwid SIBM-ESXSST336732LC____F3ET0EP0Q000072428BX1
}
6) After updating file reload the changes
service multipathd reload
7) Run following command to remove multipath device
multipath -f SIBM-ESXSST336732LC____F3ET0EP0Q000072428BX1
8) Now check if device removed from multipath
multipath
create: 3600a0b80001327d80000006d43621677 undef WINSYS,SF2372 size=12G features='0' hwhandler='0' wp=undef `-+- policy='round-robin 0' prio=1 status=undef
- 2:0:0:0 sdb 8:16 undef ready running `- 3:0:0:0 sdf 8:80 undef ready running
create: 3600a0b80001327510000009a436215ec undef WINSYS,SF2372 size=12G features='0' hwhandler='0' wp=undef `-+- policy='round-robin 0' prio=1 status=undef
- 2:0:0:1 sdc 8:32 undef ready running `- 3:0:0:1 sdg 8:96 undef ready running
...
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9) Add storage that is not supported by default as a know multipath device lets say "Vendor is HP, Product Open-V"
To add information about the HP Open-V series the entry looks like this, where %n is the device name. Add following in /etc/multipath.conf file
devices {
device {
vendor "HP"
product "OPEN-V."
getuid_callout "/lib/udev/scsi_id --whitelisted --device=/dev/%n"
}
}
To be continued..............
