Topic
  • 2 replies
  • Latest Post - ‏2010-01-31T07:27:11Z by SystemAdmin
SystemAdmin
SystemAdmin
706 Posts

Pinned topic Root on dm-multipath fails on VIOS + SLES 11

‏2010-01-28T00:36:36Z |
Hi,

I'm having trouble configuring multipath devices on root disks provided by VIOS ( 2.1.2.10-FP-22 )
in SLES 11.

http://www.ibm.com/developerworks/wikis/display/LinuxP/SLES10+-+Root+on+dmーmultipath+device?showComments=false

I've been reading this page, but it fails on the procedure where you have to rebuild the initrd

( I can't see the dm-multipath modules beeing loaded)

:~ # mkinitrd -f mpath

Kernel image: /boot/vmlinux-2.6.27.19-5-ppc64
Initrd image: /boot/initrd-2.6.27.19-5-ppc64
Root device: /dev/disk/by-id/scsi-3600a0b8000502f3c000020a54ab31348-part2 (/dev/sdb2) (mounted on / as ext3)
Kernel Modules: scsi_mod scsi_tgt scsi_transport_srp ibmvscsic crc-t10dif sd_mod uhci-hcd
Features: block usb resume.userspace resume.kernel
29509 blocks
When I enter " multipath -v 5" i see some errors while configuring the multipath device,

:~ # multipath -v 5

=========part of the output======================
Jan 28 01:55:07 | system: set ACT_CREATE (map does not exist)
Jan 28 01:55:07 | system: addmap 0 20971520 multipath 0 0 2 1 round-robin 0 1 1 8:0 1000 round-robin 0 1 1 8:16 1000

Jan 28 01:55:07 | libdevmapper: ioctl/libdm-iface.c(1691): device-mapper: reload ioctl failed: Invalid argument
Jan 28 01:55:08 | system: addmap 0 20971520 multipath 0 0 2 1 round-robin 0 1 1 8:0 1000 round-robin 0 1 1 8:16 1000

Jan 28 01:55:08 | libdevmapper: ioctl/libdm-iface.c(1691): device-mapper: reload ioctl failed: Invalid argument
Jan 28 01:55:08 | system: domap (0) failure for create/reload map
Jan 28 01:55:08 | system: remove multipath map
Jan 28 01:55:08 | sda: orphaned
Jan 28 01:55:08 | sdb: orphaned
Jan 28 01:55:08 | unloading const prioritizer
Jan 28 01:55:08 | unloading directio checker
========================================================

Here are the syslog informations

:~ # cat /var/log/messages | grep mapper

=======part of the out put==================
Jan 28 01:55:07 lparXXX kernel: device-mapper: ioctl: error adding target to table
Jan 28 01:55:07 lparXXX kernel: device-mapper: table: 253:0: multipath: error getting device
============================================

by the way, i have updated to what I believe is the latest version of multipath-tools

:~ # rpm -qa | grep multipath
multipath-tools-0.4.8-40.6.1
I've been having this problem this for quite some time, and was waiting for some information or updates to be released. However the situation hasn't changed.
For now, my question is

・Are there ANY information, configuring multipath with VIOS + SLES11 ?( Even telling me that it should work, is very helpful )

Thanks,
Updated on 2010-01-31T07:27:11Z at 2010-01-31T07:27:11Z by SystemAdmin
  • Brian_King
    Brian_King
    20 Posts

    Re: Root on dm-multipath fails on VIOS + SLES 11

    ‏2010-01-28T18:23:18Z  
    This configuration should indeed work. I've got an LPAR running with this configuration myself. First, ensure you have everything setup properly on each VIOS. Make sure the reserve policy is set to no_reserve for the backing hdisk on each VIOS. This is covered on pages 45 and 46 in the document here: http://publib.boulder.ibm.com/infocenter/systems/scope/hw/topic/iphb1_p5/iphb1pdf.pdf. Once you have the VIOS side setup, you can setup the Linux side. Take a look at the brief article here: http://www.novell.com/documentation/sles10/stor_evms/?page=/documentation/sles10/stor_evms/data/mpioroot.html. This should add the multipath driver to the initrd.
  • SystemAdmin
    SystemAdmin
    706 Posts

    Re: Root on dm-multipath fails on VIOS + SLES 11

    ‏2010-01-31T07:27:11Z  
    This configuration should indeed work. I've got an LPAR running with this configuration myself. First, ensure you have everything setup properly on each VIOS. Make sure the reserve policy is set to no_reserve for the backing hdisk on each VIOS. This is covered on pages 45 and 46 in the document here: http://publib.boulder.ibm.com/infocenter/systems/scope/hw/topic/iphb1_p5/iphb1pdf.pdf. Once you have the VIOS side setup, you can setup the Linux side. Take a look at the brief article here: http://www.novell.com/documentation/sles10/stor_evms/?page=/documentation/sles10/stor_evms/data/mpioroot.html. This should add the multipath driver to the initrd.
    Thank you very much !

    Today I've earned time to test it, and as a result I've got it running on multipath!

    Here's what I did.
    From the link you provided, I've edited the /etc/sysconfig/kernel.

    :~ # cat /etc/sysconfig/kernel | grep multipath
    INITRD_MODULES="dm-multipath"

    From this link I found that initrd does not support "user_friendly_names", so I commented it out from /etc/multipath.conf.

    http://sources.redhat.com/lvm2/wiki/MultipathUsageGuide

    after, this i ran "mkinitrd" and now I was able to see the modules being loaded.
    :~ # mkinitrd

    Kernel image: /boot/vmlinux-2.6.27.19-5-ppc64
    Initrd image: /boot/initrd-2.6.27.19-5-ppc64
    node name not found
    Root device: /dev/sda2 (mounted on / as ext3)
    Kernel Modules: scsi_mod scsi_dh dm-mod dm-multipath dm-snapshot scsi_tgt scsi_transport_srp ibmvscsic crc-t10dif sd_mod uhci-hcd dm-round-robin scsi_dh_emc scsi_dh_hp_sw scsi_dh_rdac scsi_dh_alua
    Features: dm block usb multipath kpartx resume.userspace resume.kernel
    31734 blocks

    also ran "lilo".
    After uncommenting the "user_friendly_names" in /etc/multipath.conf I've rebooted the system, and FINALLY I've got it working

    :~ # multipath -ll
    system (3600a0b8000502f3c000020a54ab31348) dm-0 AIX,VDASD
    size=10Gfeatures=0hwhandler=0rw
    \_ round-robin 0 prio=1active
    \_ 0:0:1:0 sda 8:0 activeready
    \_ round-robin 0 prio=1enabled
    \_ 1:0:1:0 sdb 8:16 activeready
    Again, thank you so much for your support!!