Duplicate LUNs in RHEL 4 (qlogic HBA)

[CA1367359]

Hi

After installing PSP (proliant support pack) on the blade servers running RHEL4 and connected to SAN switches, I see lot of duplicate LUNs ( e.g., /dev/sda, /dev/sdb, /dev/sdc, /dev/sdb all point to same SAN volume since I have two HBAs with dual ports).

In case of RHEL 3, if I use ql2xfailover=1 in /etc/modules.conf it turns off the duplicate LUNs. whats the equivalent for this?

I have recently migrated to RHEL 4 and got this issue, not seen when servers are running RHEL AS3 because of above setting.

I tried to add similiar setting in /etc/modprobe.conf but that didn't help.

Any ideas please.

[Steven E. Protter · Accepted solution]

Shalom,

A similar configuration in /etc/modeprobe.conf should help. It its not helping there may be a problem with how the SAN is presenting disk.

Is duplicate LUNS a problem? Does it not provide a means to failing over instantly?

SEP

[Ross Minkov]

In RHEL4 /etc/modules.conf is now /etc/modprobe.conf.

NB: You must enable failover multipathing for the QLogic driver in /etc/modprobe.conf before the install of

the PSP for RHEL for the QLogic driver options to be added properly to the new initrd. You can rebuild

initrd manually after the fact as well, but it is easier to handle it before.

Since you edited /etc/modprobe.conf before the install of the PSP, now you need to create a new initrd

image. Here is how you can do it.

# cd /tmp
# mkinitrd -v /tmp/ross.img `uname -r`
# cd /boot
# mv initrd-`uname -r`.img initrd-`uname -r`_ross_nofailover.img
# cp /tmp/ross.img /boot/initrd-`uname -r`.img
# ls -la

(replace ross with your name)

Take a look at /boot/grub/grub.conf (I assume you use GRUB) and make sure that the initrd line there calls

/initrd-`uname -r`.img (Note that you won't see it this way, with uname -r; it will be more like /initrd-

2.6.9-22.ELsmp.img in grub.conf).

Ideally you want to do that procedure for all of the kernels listed in grub.conf.

# reboot

After the reboot verify that the qla driver is loaded:

# lsmod | grep qla

Next verify the failover mode for the QLogic driver:

# cd /proc/scsi/qla2xxx/
# ls -la

this will show you one file per FC port; for example for a server with 3 dual ported FC HBAs:

# pwd
/proc/scsi/qla2xxx
# ls -la
total 0
dr-xr-xr-x 2 root root 0 Feb 7 13:09 .
dr-xr-xr-x 4 root root 0 Feb 7 13:09 ..
-rw-r--r-- 1 root root 0 Feb 7 14:02 0
-rw-r--r-- 1 root root 0 Feb 7 14:02 1
-rw-r--r-- 1 root root 0 Feb 7 14:02 2
-rw-r--r-- 1 root root 0 Feb 7 14:02 3
-rw-r--r-- 1 root root 0 Feb 7 14:02 4
-rw-r--r-- 1 root root 0 Feb 7 14:02 5
# grep 'Driver version' *
0: Firmware version 3.03.11 IPX, Driver version 8.00.02-fo
1: Firmware version 3.03.11 IPX, Driver version 8.00.02-fo
2: Firmware version 3.03.11 IPX, Driver version 8.00.02-fo
3: Firmware version 3.03.11 IPX, Driver version 8.00.02-fo
4: Firmware version 3.03.11 IPX, Driver version 8.00.02-fo
5: Firmware version 3.03.11 IPX, Driver version 8.00.02-fo


Note the "fo" (for fail over) at the end of each driver line. This is what we want to see here.

All done.


HTH,
Ross

[Ross Minkov]

sorry...

I said "Since you edited /etc/modprobe.conf before the install of the PSP, now you need to create a new initrd image."

it should have been:

"Since you edited /etc/modprobe.conf *AFTER* the install of the PSP, now you need to create a new initrd image."


-Ross

[Alan_152]

Is your storage device an EVA model (as opposed to an MSA)? The EVA does have this issue documented.

As a start, though, I would make sure that both the firmware and the driver for the QLA are up to date.

[Jorge Cocomess]

Disconnect one Fibre connection and reboot your server. Once the server came back online, at the terminal prompt, type dmesg > sysinfo

Now, you can display this file and see all of your luns that was exposed to your server (sda, sdb, sdc, etc).

Now, you can read up and perhaps look more into Secured Path - If you're using Qlogic HBA, you can use their driver to do what you have intended.

Do let us know the results.

Take care!

[CA1367359]

Hi,

Thanks to all of you.

The solution I worked out it is :

Reinstall proliant support pack (PSP) as below:

1. Extract the PSP packages to a directory and from that run these two commands.

echo â HPQLA2X00FO=QLogicFailover" > /tmp/pspopt
./install740.sh --verbose --nui --force --inputfile /tmp/pspopt

2. Reboot the server

Now you can see only unique LUNs.

Thanks again to all who responded to my post.

[CA1367359]

My problem is resolved, I am closing this thread.