When I execute `multipath -v3` the following appears in /var/log/messages: Jan 29 16:32:50 svwdcvispay01 kernel: device-mapper: dm-multipath: error getting device Jan 29 16:32:50 svwdcvispay01 kernel: device-mapper: error adding target to table Jan 29 16:32:52 svwdcvispay01 hald[3620]: Timed out waiting for hotplug event 361. Rebasing to 362 Jan 29 16:33:06 svwdcvispay01 hal.hotplug[22665]: timout(10000 ms) waiting for /block/dm-5 I am able to perform I/O to both /dev/sda and /dev/sdc: [root@svwdcvispay01 ~]# dd if=/dev/sda of=/dev/null count=10 10+0 records in 10+0 records out [root@svwdcvispay01 ~]# dd if=/dev/sdc of=/dev/null count=10 10+0 records in 10+0 records out [root@svwdcvispay01 ~]# Joe Little littlej@xxxxxx -----Original Message----- From: dm-devel-bounces@xxxxxxxxxx [mailto:dm-devel-bounces@xxxxxxxxxx] On Behalf Of malahal@xxxxxxxxxx Sent: Tuesday, January 29, 2008 2:58 PM To: dm-devel@xxxxxxxxxx Subject: Re: Problem using dm-multipath on first of 2 LUNs on system LittleJ@xxxxxx [LittleJ@xxxxxx] wrote: > I am attempting to implement dm-multipath on a RHEL4U6 server and I have > been successful in enabling it on the second of 2 LUNs on the server but > for whatever reason it will not create the device special files in > /dev/mapper for the fist LUN. `multipath -d` shows that it identifies the > first LUN and wants to create the mpath0 files: > > > > [root@svwdcvispay01 etc]# multipath -d > > create: mpath0 (36005076801810085c800000000000194) > > [size=12 GB][features="1 queue_if_no_path"][hwhandler="0"] > > \_ round-robin 0 [prio=50] > > \_ 1:0:0:0 sda 8:0 [ready] > > \_ round-robin 0 [prio=10] > > \_ 1:0:1:0 sdc 8:32 [ready] One of the fields (DM path state) is missing from the above output. Looks like it failed to create mpath0 properly. Make sure you enable 'syslog' and send out the syslog out when you run "multipath -v3" Also, can you do read/write I/O to sda and sdc devices? Try reading data from both of those devices using dd or something similar. The following should do: dd if=/dev/sda of=/dev/null count=10 dd if=/dev/sdc of=/dev/null count=10 Thanks, Malahal. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
