Problem: Qlogic Fiber Channel HBA + Sansurfer that suports failover does not
         work with on Linux with E-class running firmware 2.28.0000.00 or later.

In this example there is one LUN on the subsystem and 2 paths to the subsystem.

        [root@localhost ~]# fdisk -l

        Disk /dev/sda: 21.4 GB, 21475491840 bytes
        64 heads, 32 sectors/track, 20480 cylinders
        Units = cylinders of 2048 * 512 = 1048576 bytes

        Disk /dev/sda doesn't contain a valid partition table

        Disk /dev/sdb: 21.4 GB, 21475491840 bytes
        64 heads, 32 sectors/track, 20480 cylinders
        Units = cylinders of 2048 * 512 = 1048576 bytes

        Disk /dev/sdb doesn't contain a valid partition table

        Disk /dev/sdc: 250.0 GB, 250059350016 bytes

With sansurfer failover enabled you should see only /dev/sda as the Qlogic driver is providing the failover, instead we see the same LUN twice as /dev/sda and /dev/sdb.

=====================================================================

Solution: From the serial port or telnet as administrator enter the
          following command

        -------------------------------------------------------------
        Promise VTrak Command Line Interface (CLI) Utility
        Version: 3.31.0000.00 Build Date: Nov 26, 2008
        -------------------------------------------------------------

        Login: administrator
        Password: *
        -------------------------------------------------------------
        Type help or ? to display all the available commands
        Type menu to enter Menu Driven Configuration Utility
        -------------------------------------------------------------

        administrator@cli> ctrl -a mod -s "commonwwnn=enable"

        administrator@cli> shutdown -a restart

The subsystem must be restarted for this setting to take effect.

If failover is already configured you should see only /dev/sda after the reboot.

        [root@localhost ~]# fdisk -l

        Disk /dev/sda: 21.4 GB, 21475491840 bytes
        64 heads, 32 sectors/track, 20480 cylinders
        Units = cylinders of 2048 * 512 = 1048576 bytes

        Disk /dev/sda doesn't contain a valid partition table

        Disk /dev/sdc: 250.0 GB, 250059350016 bytes

====================================================================

Discussion:

The default setting for the commonwwnn was changed at E-class firmware version 3.28.0000.00 on up.

If your unit had older firmware the old setting may persist unless the "factorydefaults" are reset on the subsystem by the administrator (please see the product user manual on setting factory defaults)