Questions About Configuring Multipath Devices into Logical Volume [Linux]

[jonp27]

I'm trying to create a logical volume in RHEL 5 from a volume on my Nimble SAN.

Where I am lost is, once multipathing is configured and both NICs are bound to the software iSCSI initiator, I see two multipath devices showing in fdisk (dm-2 and dm-3).

Do I partition both devices and add them into a single logical volume, or have I done something wrong?

What I have done so far (following the guide provided by Nimble):

• Created the volume on the Nimble and assigned the initiator group from the Linux host to it.
• Configured both NICs (separate subnets) and bound them to the iSCSI software initiator.
• Configured multipathing.
• Discovered targets.
• Logged into targets.

[aherbert23 · Accepted solution]

You might try reviewing the following articles. The second article will help you know which device is which by using the IQN of the volume as the device alias. So instead of you looking for /dev/dm-* you can look under /dev/mapper like this:

ls -l /dev/mapper/ 

total 0 

crw------- 1 root root 10, 236 Dec 17 08:48 control 

lrwxrwxrwx 1 root root       7 Dec 17 13:28 mysql-clone-v16da9ef36265f874.000001dd.74bf6687-lun-0 -> ../dm-2 

lrwxrwxrwx 1 root root       7 Dec 17 13:28 mysql-clone-v16da9ef36265f874.000001dd.74bf6687-lun-0-part1 -> ../dm-3

MPIO Settings for Linux

Use IQN string as device name in Linux with multipathing

[jonp27]

Thanks, Adam! I had followed your guide initially, and found it extremely helpful. I was definitely looking in the wrong place for the multipath device.