How to create Oracle ASM devices using device-mapper multipath devices in Red Hat Enterprise Linux 6?
环境
Red Hat Enterprise Linux 6
Device-Mapper Multipath (DM Multipath)
Oracle ASM
Udev
决议
Please use the following steps to create Oracle ASM disks with dm-multipath on RHEL 6 systems:
Determine the DM_UUID value for each multipath device that is required to be used for Oracle ASM. You could use following command for the same:
$ udevadm info --query=all --name=/dev/mapper/mpathN |grep -i DM_UUID
Please replace mpathN in above command with name of the multipath devices used in your setup/environment.
The output of above command would be similar to the one shown below:
$ udevadm info --query=all --name=/dev/mapper/mpathd|grep -i DM_UUID
E: DM_UUID=mpath-1234567890abcdefghijklmnopqrstuvwxyz
Above command would be required to be repeated for each multipath device to be used with Oracle ASM, and please note down the DM_UUID value retrieved for each multipath device. This value would be used to create udev rule.
Create a udev rule file /etc/udev/rules.d/96-asmmultipath.rules and add a udev rule for each multipath device using it's DM_UUID value:
ACTION=="add|change", ENV{DM_UUID}=="mpath-<UUID>", SYMLINK+="oracleasm/asm01", GROUP="dba", OWNER="oracle", MODE="0660"
e.g. to create Oracle ASM disk /dev/oracleasm/asm01 using above multipath device mpathd following udev rule could be used:
$ cat /etc/udev/rules.d/96-asmmultipath.rules
ACTION=="add|change", ENV{DM_UUID}=="mpath-1234567890abcdefghijklmnopqrstuvwxyz", SYMLINK+="oracleasm/asm01", GROUP="dba", OWNER="oracle", MODE="0660"
Note that we have replaced mpath-<UUID> in above rule with the DM_UUID retrieved in step [1]. Similarly a udev rule for each multipath device would be required to be appended in /etc/udev/rules.d/96-asmmultipath.rules file.
You could also modify Symlink path (e.g. oracleasm/asm01 in above udev rules), Group, Owner permissions as per requirement.
Reload the udev service for the changes to take effect and create the ASM disks.
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