Oracle Database Oracle 12cR1 184.108.40.206.0 Enterprise Edition
Operating System(s) Red Hat Enterprise Linux with kernel 2.6.32-431.el6.x86_64
Storage EqualLogic Storage Array PS6110
How to configure multipath for EqualLogic Storage Array PS6110?
Device mapper multipath utility is used to achieve consistent naming of shared volumes across all nodes in a RAC set up.
The four components of a multipath configuration file are:
- blacklist exceptions
- defaults &
The wiki article How to configure device-mapper-multipath
provides the steps involved in configuring the /etc/multipath.conf file. However for the purpose of deploying the Oracle RAC12cR1 on RHEL 6.5, with EqualLogic PS6110 as the storage, the defaults section of the multipath configuration file needs to have the values given below:
path_selector "round-robin 0"
getuid_callout "/lib/udev/scsi_id --whitelisted --device=/dev/%n"
Of particular interest is the path checker attribute which specifies the default method used to determine the state of the paths. If it is set to read sector0 it reads the first sector of the device. When set to a value of "tur" Test Unit Ready, it issues a TUR to the device. For Equallogic PS 6110 the path checker attribute needs to be set to "tur".