IBM DS3000

Chapter 21. FC configuration 3 - Linux SAN boot with System x 3755 519
Draft Document for Review August 30, 2007 12:59 am 7065FC_Config3.fm
kernel /vmlinuz-2.6.9-34.ELsmp ro root=LABEL=/ pci=nommconf rhgb quiet
initrd /mpp-2.6.9-34.ELsmp.img
3. Restart the system using the new boot option.
21.7.3 Verification
When the server restarts, use the lsmod command to verify that the RDAC (MPP) modules
are running. The following modules should be listed:
򐂰 mppUpper
򐂰 mppVhba
򐂰 sg
򐂰 sd_mod
򐂰 scsi_mod
Run:
ls -lR /proc/mpp
This command produces output similar to Example 21-7:
Example 21-7 ls -lR /proc/mpp output
/proc/mpp:
total 0
dr-xr-xr-x 3 root root 0 Jun 20 17:08 DS3400_Thailand
/proc/mpp/DS3400_Thailand:
total 0
dr-xr-xr-x 3 root root 0 Jun 20 17:08 controllerA
-rw-r--r-- 1 root root 0 Jun 20 17:08 virtualLun0
/proc/mpp/DS3400_Thailand/controllerA:
total 0
dr-xr-xr-x 2 root root 0 Jun 20 17:08 qla2xxx_h1c0t0
/proc/mpp/DS3400_Thailand/controllerA/qla2xxx_h1c0t0:
total 0
-rw-r--r-- 1 root root 0 Jun 20 17:08 LUN0
-rw-r--r-- 1 root root 0 Jun 20 17:08 UTM_LUN31
As you can see, RDAC is communicating with the DS3400 subsystem. However, it can only
talk to controller A at this time. This is because only one I/O path is configured. To enable
multipath, there is one final step - configure the I/O path between FC HBA port 1 and DS3400
controller B.
21.8 Enabling the second I/O path
First we change the effective SAN switch configuration. Up to now, the effective configuration
was x3755_CtrlA_only, as defined in21.3, “SAN switch zoning for the first I/O path” on
page 499.