AIM - How to configure multipathing on Red Hat Enterprise Linux 5 Linux iSCSI booted personas

Table of Contents:

1. Additional Information
2. Configure Multipathing

The AIM documentation is not clear on how to configure iSCSI booted Red Hat Enterprise Linux 5 personas in a multipath environment.

The format for the boot device is supplied but there is no information on how to pass the iSCSI volume SCSI ID to the ramdisk during the boot process. There is no information on how to create additional iSCSI sessions that will be used by the device mapper.

The following procedure will be incorporated into the core AIM documentation..

To configure multipathing, perform the following steps:

1. Install Red Hat Enterprise Linux 5 on a server’s local disk
2. Install the AIM persona agent
3. Prevent the AIM service from running at boot time
4. Create a volume on the iSCSI target and provide access to the desired iSCSI initiator
5. Configure the iSCSI initiator on the Linux image
6. Discover the iSCSI target and login to the iSCSI volume
7. Verify that the iSCSI volume is visible
8. Migrate the Linux image from local disk to an iSCSI volume with copy_persona.sh in the standard fashion
9. Generate the ramdisk and copy it to the controller along with the kernel (only required if this is the initial persona using this kernel revision)
10. Mount the iSCSI volume
11. Get the SCSI ID of the iSCSI volume
12. Update /etc/fstab with the multipath device
13. Add the persona to the AIM environment
14. Shut down the source image
15. Boot the persona on a targeted server
16. Start the persona agent and configure it to start automatically
17. Verify that the multipath device is in use
18. Add an iSCSI interface for both boot interfaces on the persona
19. Re-discover the iSCSI portal
20. Create additional iSCSI sessions
21. List the iSCSI sessions
22. Configure /etc/rc.local for running multipath which scans for available paths
23. Reboot the persona
24. Confirm that multiple paths are now in use for the boot LUN
25. Boot the persona from both boot NICs and confirm that multiple sessions are available

A detailed procedure is attached.