DS4300 Turbo

[David Sung Min Joo <djoo@redhat.com>]

Dear all,

I just had a case where, I setup dm-multipath with DS4300-turbo (Dual
controller) with failover.
However with CLVM, whenever I try to check VGs with vgscan it would take
more than 3 mins.

Then in the /var/log/messages, I would see paths being dropped resulting
not having any path to the storage, and after few retries within
themselves, the right VGs will be shown.
However, I am very worried with outputs;
Jun 16 06:52:20 aigwebmail kernel: device-mapper: dm-multipath: Failing
path 8:16.
Jun 16 06:52:20 aigwebmail multipathd: 8:16: tur checker reports path is
down
Jun 16 06:52:20 aigwebmail multipathd: checker failed path 8:16 in map
4300-0
Jun 16 06:52:20 aigwebmail multipathd: 4300-0: remaining active paths: 1
Jun 16 06:52:21 aigwebmail multipathd: 8:144: tur checker reports path
is down
Jun 16 06:52:21 aigwebmail multipathd: checker failed path 8:144 in map
4300-0
Jun 16 06:52:21 aigwebmail kernel: device-mapper: dm-multipath: Failing
path 8:144.
Jun 16 06:52:31 aigwebmail multipathd: 4300-0: remaining active paths: 0
Jun 16 06:52:31 aigwebmail multipathd: 8:16: tur checker reports path is up
Jun 16 06:52:31 aigwebmail multipathd: 8:16: reinstated
Jun 16 06:52:31 aigwebmail multipathd: 4300-0: remaining active paths: 1
Jun 16 06:52:31 aigwebmail multipathd: 8:144: tur checker reports path is up
Jun 16 06:52:31 aigwebmail multipathd: 8:144: reinstated
Jun 16 06:52:31 aigwebmail multipathd: 4300-0: remaining active paths: 2
Jun 16 06:52:42 aigwebmail multipathd: 8:160: tur checker reports path
is down
Jun 16 06:52:42 aigwebmail multipathd: checker failed path 8:160 in map
4300-1
Jun 16 06:52:42 aigwebmail kernel: device-mapper: dm-multipath: Failing
path 8:160.
Jun 16 06:52:52 aigwebmail multipathd: 4300-1: remaining active paths: 1
Jun 16 06:52:52 aigwebmail multipathd: 8:160: tur checker reports path is up
Jun 16 06:52:52 aigwebmail multipathd: 8:160: reinstated
Jun 16 06:52:52 aigwebmail multipathd: 4300-1: remaining active paths: 2

FYI,

multipath.conf

defaults {
	multipath_tool 		"/sbin/multipath -v0"
	udev_dir     		/dev
	polling_interval	10
	selector     		"round-robin 0"
	path_grouping_policy	failover
	getuid_callout 		"/sbin/scsi_id -g -u -s /block/%n"
	prio_callout		"/bin/true"
	path_checker		tur
	rr_wmin_io		100
	failback		immediate
	user_friendly_names	yes
}
....
devnode_blacklist {
       wwid 26353900f02796769
	devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
	devnode "^hd[a-z][0-9]*"
	devnode "^cciss!c[0-9]d[0-9]*"
	devnode "sda"

Regards,
David Joo
}