[CentOS] multipathd

Wed Feb 4 14:02:32 UTC 2015
Rushton Martin <JMRUSHTON at qinetiq.com>

Our cluster was supplied with two IBM DS3400 RAID arrays connected with
fibre channel.  Both are old and one is failing so we bought an IBM
V3700 to replace it.  The V3700 complained that we were using the IBM's
RDAC driver (true) and we were advised to change to using Linux
multipath.  I've done that but the default configuration for the DS3400s
is:
        device {
                vendor IBM
                product 1726-4xx
                path_checker rdac
                features 1 queue_if_no_path
                hardware_handler 1 rdac
                prio_callout /sbin/mpath_prio_rdac /dev/%n
                no_path_retry 300
                rr_min_io 1000
        }
The V3700 is still complaining and I note the "path checker rdac" and
mpath_prio_rdac lines.  Is this rdac the same as IBM's RDAC, and if so
how can I get rid of it?

OS is CentOS 5.3 (yes, I know - upgrade), filesystem is GPFS.
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