Hi Jeff, in Oracle Clusterware, RAC and ASM you have to use RAW devices - as you mentioned. In Linux you have to bind the SCSI block devices to a RAW device. In RedHat: # vi /etc/sysconfig/rawdevices /dev/raw/raw1 /dev/disk/by-name/1HITACHI_D60085320025 /dev/raw/raw2 /dev/disk/by-name/1HITACHI_D60085320018 In Suse: # vi /etc/raw raw1:disk/by-name/1HITACHI_D60085320025 raw2:disk/by-name/1HITACHI_D60085320018 After restarting the RAW subsystem you only work with /dev/raw/raw.*. The mapper device name is fixed and depends on the storage type, serial number and storage internal lun number. With the binding also the RAW device names are fixed. In Oracle ASM you enter /dev/raw/raw.* and the complete path is binded. If you use the Oracle ASMlib (easy to install) you do not need to bind the RAW devices. Example: # multipath -ll 1HITACHI_D60H02610121 [size=1 GB][features="0"][hwhandler="0"] \_ round-robin 0 [prio=1][active] \_ 1:0:1:1 sdj 8:144 [active][ready] \_ round-robin 0 [enabled] \_ 2:0:1:1 sdan 66:112 [active][ready] # /etc/init.d/oracleasm createdisk DISK1 /dev/disk/by-name/1HITACHI_D60H02660121 Marking disk "/dev/disk/by-name/1HITACHI_D60H02660121" as an ASM disk: done # /etc/init.d/oracleasm listdisks DISK1 # /etc/init.d/oracleasm querydisk DISK1 Disk "DISK1" is a valid ASM disk on device [253, 6] SHUTDOWN the server Exchange the LUN number with another LUN for an different scanning sequence. BOOT the server Now other major and minor numbers are used: # multipath -l 1HITACHI_D60H02610121 [size=1 GB][features="0"][hwhandler="0"] \_ round-robin 0 [active] \_ 1:0:1:0 sdi 8:128 [active][ready] \_ round-robin 0 [enabled] \_ 2:0:1:0 sdam 66:96 [active][ready] # /etc/init.d/oracleasm listdisks DISK1 # /etc/init.d/oracleasm querydisk DISK1 Disk "DISK1" is a valid ASM disk on device [8, 32] # /etc/init.d/oracleasm querydisk /dev/disk/by-name/1HITACHI_D60H02660121 Disk "/dev/disk/by-name/1HITACHI_D60H02660121" is marked an ASM disk with the label "DISK1" No problem for ASM to find the correct disk. Regards, Matthias -- dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel