Hi Alexander,

thanks for replying, here's my current multipath.conf:

defaults { user_friendly_names yes }

blacklist { devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*" devnode "^(hd|xvd|vd)[a-z]*" wwid "*" }

blacklist_exceptions { wwid "3600144f0fdf58b5c00004bc738070001"

    devices{
            device {
             vendor "SUN"
             product "Sun Storage 7310"
            }
    }

}

devices { device { vendor "SUN" product "Sun Storage 7310" path_grouping_policy failover getuid_callout "/sbin/scsi_id -g -u -s /block/%n" prio_callout "/sbin/mpath_prio_rdac /dev/%n" features "0" failback immediate rr_weight uniform no_path_retry queue rr_min_io 1000 } }

I added "path_grouping_policy failover" because of your message. I also noticed, you have path_grouping_policy specified twice; is this on purpose?

Sorry, that was a copy&paste&adjustment error on my side. Just decide for 1 path_grouping_policy. You can find details about possible settings on

http://www.centos.org/docs/5/html/5.2/DM_Multipath/config_file_devices.html

Also, when I activate 'hardware_handler "1 rdac"', the box does not boot any more with some rdac driver error message that I can catch since it scrolls by fast...

Ok, take it out then.

with the above multipath.conf it gets even stranger:

[root@dev-db1 ~]# multipath -ll sdd: checker msg is "readsector0 checker reports path is down" sdh: checker msg is "readsector0 checker reports path is down" sdi: checker msg is "readsector0 checker reports path is down" sdj: checker msg is "readsector0 checker reports path is down"

Did you try by setting following option?

path_checker rdac

C9 Inquiry of device </dev/sda> failed. C9 Inquiry of device </dev/sde> failed. mpath0 (3600144f0fdf58b5c00004bc738070001) dm-0 SUN,Sun Storage 7310 [size=50G][features=1 queue_if_no_path][hwhandler=0][rw] _ round-robin 0 [prio=0][active] _ 0:0:1:0 sda 8:0 [active][ready] _ 1:0:0:0 sde 8:64 [active][ready]

At least I see 1 path group with 1 path per HBA for the LUN you have whitelisted.

however, the system "lives happily", despite the error messages.

Did you test so far a failover case? Does the other paths come up if the active ones fail?

What device-mapper-multipath knows about SUN storage system by compiled in default values can be queried by

multipathd -k"show config" | grep -A8 -B1 "SUN"

Ah, while coming to an end with this mail and considering to check upstream (http://christophe.varoqui.free.fr/) whether they know about your specific storage device, I found the infos you need to configure!

wikis.sun.com/download/attachments/186238602/2010_Q1_ADMIN.pdf

Page 107+108 gives you all required / SUN recommended settings:

device { vendor "SUN" product "Sun Storage 7310" getuid_callout "/sbin/scsi_id -g -u -s /block/%n" prio_callout "/sbin/mpath_prio_alua /dev/%n" hardware_handler "0" path_grouping_policy group_by_prio failback immediate no_path_retry queue rr_min_io 100 path_checker tur rr_weight uniform }

I guess ALUA is enabled by default on the SUN storage 7310, but check it.

Jens Neu Health Services Network Administration

Regards

Alexander