Specifications

The output should resemble the following:
[root@devices] # scsi_id -g -s /block/sdc
*3600a0b80001327510000015427b625e*
This long string of characters is the UUID. To get the device names to key off the UUID, check
each device path to ensure that the UUID number is the same for each device. The UUIDs do
not change when you add a new device to your system. Once you have checked the device
paths, you must create rules for the device naming. To create these rules, you must edit the
20-names.rules file that resides in the /etc/udev/rules.d directory. The device naming
rules you create here should follow this format:
# KERNEL="sd*", BUS="scsi", PROGRAM="sbin/scsi_id", RESULT="UUID",
NAME="devicename"
Replace your exisiting UUID and devicename with the above UUID retrieved entry. So the rule
should resemble the following:
KERNEL="sd*", BUS="scsi", PROGRAM="sbin/scsi_id",
RESULT="3600a0b80001327510000015427b625e
", NAME="mydevicename"
This causes the system to enable all devices that match /dev/sd* to inspect the given UUID.
When it finds a matching device, it creates a device node called /dev/devicename. For this
example, the device node is /dev/mydevice . Finally, you need to append the rc.local file
that resides in the /etc directory with this path:
/sbin/start_udev
IMPLEMENTING LUN PERSISTENCE WITH MULTIPATH
To implement lun persistence in a multipath environment, you must define the alias names for
the multipath devices. For this example, you must define four device aliases by editing the
multipath.conf file that resides in the /etc/ directory:
multipath {
wwid 3600a0b80001327510000015427b625e
alias oramp1
}
multipath {
wwid 3600a0b80001327510000015427b6
Implementing Lun Persistence
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