Enabling MPXIO on Solaris 10

Solaris MPxIO provides a multipathing solution for storage devices accessible through multiple physical paths.  Multipathing provides the ability to set up multiple redundant paths to a storage system and gives you the benefits of load balancing and failover. MPxIO was initially delivered on SPARC Systems mostly on fibre attached storage. It abstracts physical paths to a device, providing unified access via a single virtual device. Physical path failures are transparently recovered, so failures are not exposed to the applications using the virtual device.

The scsi_vhci driver registers with the MPxIO framework. It is the virtual host controller providing the abstraction for SCSI protocol devices.

To enable it, edit the file /kernel/drv/fp.conf file.

mpxio-disable="yes";

Change yes to no and it will be enabled:


sys01# cat /kernel/drv/fp.conf
#
# Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
.
.<truncated>
.
mpxio-disable="no";
disable-sata-mpxio="no";


Then issue this command.

sys01# stmsboot -e 

Following this enabling, you are prompted to reboot. During the  reboot,  vfstab  and  the  dump configuration  will be updated to reflect the device name changes.


There are three ways to check that everything is fine.

1. Look for log messages in /var/adm/messages.

As the machine comes up, you should see a message like:

Dec 18 11:42:24 sys01 mpxio: [ID 669396 kern.info]
/scsi_vhci/ssd@g60060e8005b237000000b3480000087c (ssd11)
multipath status: optimal, path /pci@9,600000/SUNW,qlc@1/fp@0,0
(fp1) to target address: 60070f9006c34826,0 is online.
Load balancing: round-robin

If everything's fine, you should see an optimal status. If there's a problem you should see a degraded status.
Watch out for messages like "lost all paths", we dont want to see that.


2. Using mpathadm command. Just check the "Path State:", it will say if its ok or not.

sys01# mpathadm show lu /dev/rdsk/c3t60060E8005B237000000B3480000087cd0s2
Logical Unit:  /dev/rdsk/c3t60060E8005B237000000B3480000087cd0s2
        mpath-support:  libmpscsi_vhci.so
        Vendor:  HITACHI
        Product:  OPEN-V      -SUN
        Revision:  6007
        Name Type:  unknown type
        Name:  60060e8005b237000000b3480000087c
        Asymmetric:  no
        Current Load Balance:  round-robin
        Logical Unit Group ID:  NA
        Auto Failback:  on
        Auto Probing:  NA

        Paths: 
                Initiator Port Name:  10000000d082a05c
                Target Port Name:  60070f9006c34826
                Override Path:  NA
                Path State:  OK
                Disabled:  no

                Initiator Port Name:  10000000d082a05b
                Target Port Name:  50060e8005b23705
                Override Path:  NA
                Path State:  OK
                Disabled:  no

        Target Ports:
                Name:  60070f9006c34826
                Relative ID:  0

                Name:  50060e8005b23705
                Relative ID:  0


3. Using luxadm command. Just check the "State:", it will say if its online or not.

sys01# luxadm display /dev/rdsk/c3t60060E8005B237000000B3480000087cd0s2
DEVICE PROPERTIES for disk: /dev/rdsk/c3t60060E8005B237000000B3480000087cd0s2
  Vendor:               HITACHI
  Product ID:           OPEN-V      -SUN
  Revision:             6007
  Serial Num:           60 0C348087C
  Unformatted capacity: 41679.141 MBytes
  Write Cache:          Enabled
  Read Cache:           Enabled
    Minimum prefetch:   0x0
    Maximum prefetch:   0x0
  Device Type:          Disk device
  Path(s):

  /dev/rdsk/c3t60060E8005B237000000B3480000087cd0s2
  /devices/scsi_vhci/ssd@g60060e8005b237000000b3480000087c:c,raw
   Controller           /devices/pci@0/pci@0/pci@8/SUNW,emlxs@0,1/fp@0,0
    Device Address              60070f9006c34826,1
    Host controller port WWN    10000000d082a05c
    Class                       primary
    State                       ONLINE
   Controller           /devices/pci@0/pci@0/pci@8/SUNW,emlxs@0/fp@0,0
    Device Address              50060e8005b23705,1
    Host controller port WWN    10000000d082a05b
    Class                       primary
    State                       ONLINE