FC SAN multipath I/O error slow down everything, udev blacklist needed?

[Francesco Provino]

Hi folks, I got two IBM x3550M4 with Emulex double-8gbit FC cards and one IBM DS3512 FC SAN directly connected.
I've setup multipath correctly (from IBM papers for linux) and blacklisted the devices in lvm.conf.
CentOS works great and gives absolutely NO errors.
With exactly the same configuration of multipath.conf and lvm.conf, ProxMox gets lots of I/O errors on startup (dramatically slowed down due to thousands of errors) and also every "n" seconds, causing incostant performance compared to CentOS.
It seems like udev is trying to get information about the "fake" devices sdb and sdc (used for multipath).
I discovered that ProxMox and CentOS have exactly the same version of lpfc drivers.

What would you suggest?

 

[tom]

also check http://pve.proxmox.com/wiki/ISCSI_Multipath

 

[Francesco Provino]

also check http://pve.proxmox.com/wiki/ISCSI_Multipath

Already checked, thanks. Everything described in that page works perfectly.
I think it's more udev/module loading problem like this: https://www.ibm.com/developerworks/forums/thread.jspa?threadID=394562 .

 

[M@ario]

Hi!

I had a similiar configuration (IBM DS4700). Don't know if it works with the DS3512 too, but you can try the following (but better backup your initrd first)...

In /etc/initramfs-tools/initramfs.conf change MODULES=most to MODULES=dep
In /etc/initramfs-tools/modules add scsi_dh_rdac
update-initramfs -u -k all
reboot

 

[Francesco Provino]

Hi!

I had a similiar configuration (IBM DS4700). Don't know if it works with the DS3512 too, but you can try the following (but better backup your initrd first)...

In /etc/initramfs-tools/initramfs.conf change MODULES=most to MODULES=dep
In /etc/initramfs-tools/modules add scsi_dh_rdac
update-initramfs -u -k all
reboot

Thank you, now everything works fine!

 

[Francesco Provino]

[SOLVED]

Thanks a lot!