Hi Roberto. You can use the emcpadm() command to rename the device on each node so they are all the same. The syntax is "emcpadm rename[pseudo] -s src pseudodevice -t tgt pseudodevice". For example, if on node A the device is emcpowerg and you wish it to be be emcpowerq you would issue: # emcpadm rename -s emcpowerg -t emcpowerq For each node run the "powermt display dev=all" and review the Logical device ID that is displayed for each LUN on each node. Find your quorom disk on each - for example, Logical device ID=6006016018C80800B5069570B8A9D911 # powermt display dev=emcpowerg Pseudo name=emcpowerg CLARiiON ID=WRE00100100415 Logical device ID=6006016018C80800B5069570B8A9D911 state=alive; policy=CLAROpt; priority=0; queued-IOs=0 Owner: default=SP A, current=SP A ====================================================================== ------------ Host ----------- - Stor - -- I/O Path - -- Stats --- ### HW Path I/O Paths Interf. Mode State Q-IOs Errors ====================================================================== 3 lpfc sdaa SP A0 active alive 0 0 2 lpfc sdj SP A1 active alive 0 0 Then rename it.... # emcpadm rename -s emcpowerg -t emcpowerq ...and your in business. Regards, Wayne. -----Original Message----- From: linux-cluster-bounces@xxxxxxxxxx [mailto:linux-cluster-bounces@xxxxxxxxxx] On Behalf Of Roberto Fratelli Sent: Monday, April 27, 2009 9:18 AM To: linux-cluster@xxxxxxxxxx Subject: Persistent naming with UDEV and EMC's Powerpath Hello everyone ! I'm trying to set up a quorum disk in a 2-node redhat cluster (RHEL 4.7). Both nodes are attached to a SAN Clariion over qlogic HBA's and i'm using EMC's powerpath. The problem i'm facing is that the disks's device names are different across the nodes. For example, the lun i elected to be my quorum disk is called '/dev/emcpowerf' at node-a and '/dev/emcpowerd' at node-b, so i can't use the device name (/dev/emcpowerXX) in my cluster.conf file. In a attempt to overcome this i've tried to use the disk label instead : <quorumd label="97196ef0-da2f-4b79-a5c5-999dce70d677" interval="2" tko="10" votes="1"/> But did not work also, because this way it finds '/dev/sdXX' before '/dev/emcpowerXX': root@node-a:~ # cman_tool nodes Node Votes Exp Sts Name 0 1 0 M /dev/sdf1 1 1 2 M node-a 2 1 2 M node-b root@node-a:~ # Since this '/dev/sdf' is just one of the paths i have under powerpath (it has 4 paths per HBA, 8 paths per lun total) i can't keep it this way because in a event of lun trespass (clariion does it very often) i would loose quorum. My understanding is that i need some kind of "persistent binding" so i can use Powerpath's pseudo-device '/dev/emcpowerXX', so i tried to create a UDEV rule like this: [root@node-a RSM]# cat 75-quorum.rules KERNEL=="emcpower[a-z]1, SYSFS{label}=="97196ef0-da2f-4b79-a5c5-999dce70d677", SYMLINK+="discodequorum%n" [root@node-a RSM]# Which did not worked, i think because UDEV starts way before powerpath. Does anyone here faced this problem before ? how can i keep the device names persistent across the nodes (at least for the quorum disk) ? Below some more info on my quorum's disk: root@node-a:~ # mkqdisk -L mkqdisk v0.5.2 /dev/sdf1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdo1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdx1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdag1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdap1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sday1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdbh1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdbq1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/emcpowerf1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 root@node-a:~ # [root@node-b ~]# mkqdisk -L mkqdisk v0.5.2 /dev/sdf1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdo1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdx1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdag1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdap1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sday1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdbh1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/sdbq1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 /dev/emcpowerd1: Magic: eb7a62c2 Label: 97196ef0-da2f-4b79-a5c5-999dce70d677 Created: Mon Dec 24 11:47:11 2007 Host: node-a Kernel Sector Size: 512 [root@node-b ~]# -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
