[PVE-User] qla2xxx, IBM DS4300 and multipath on proxmox troubles

[Lorenzo Quatrini]

Hi all,
I'm on the process of migrating several servers to Proxmox.
Original setup was on an IBM blade server: six blades with windows 2003 server,
Qlogic fiber-channel, connection to an external DS4300 storage.
The DS4300 doesn't support partitioning, so I can only chose one host type.
Now I installed proxmox on a couple of blades, migrating the hdd using dd to LVM.
I have a problem with multipath, the DS4300 host type and fc LUN: I'm unable to
find a stable setup.
I get tons of
> sd x:y:z:t: reservation conflict
> sd x:y:z:t: [sdX] Result: hostbyte=DID_OK driverbyte=DRIVER_OK,SUGGEST_OK
> end_request: I/O error, dev sdX, sector 0
for each LUN which is currently used from the remaining windows servers;
If I don't enable multipath LVM also complains about duplicate disk, and the
system is slow each time it tries to access the disks (eg. by lvscan, pvscan,
blkid and so on).
If I don't enable multipath proxmox, even if the web interface is slow, is able
to boot the KVM guests.
If I remove the problematic LUN (echoing "scsi remove-single-device x y z t >
/proc/scsi/scsi") all the messages (and slowliness) goes away until next
reboot: I'm also able to start multipathd and everything looks fine.
If I boot with multipath enable (multipath.conf:
http://pastebin.centos.org/31406) the system hangs on boot.

So: I would like to know if someone has suggestion on multipath.conf and host
type configuration for the DS4300 das;
If there is a way to remove automagically (or to exclude) the failing LUN from
scsi at boot time (btw, they may change the order, changing HN or kernel version)
Or in general if you have suggestion on making the above system more stable.

Let me know if you need more information.
TIA
Regards
Lorenzo Quatrini