###############################################################################
# Multipath.conf file for IBM Storage 
#
# Version 3.01
#
# IMPORTANT: If you change multipath.conf settings after the DM MPIO devices
# have already been configured, be sure to rerun "multipath".
###############################################################################
#
#
# defaults:
#
#     polling_interval   : The interval between two path checks in seconds.
#
#     failback           : The failback policy should be set to "immediate"
#                          to have automatic failback, i.e. if a higher
#                          priority path that previously failed is restored,
#                          I/O automatically and immediately fails back to 
#                          the preferred path.
#
#    no_path_retry       : Use this setting in order to deal with transient
#                          total path failure scenarios. Indicates that the if
#                          all paths are failed for 10 checks (iterations of
#                          the checkerloop) then will set the device to
#                          .fail_if_no_path. so that I/O will not stay queued
#                          forever and I/O errors are returned back to the
#                          application. This value should be adjusted based on
#                          the value of the polling_interval. Basically, with a
#                          larger polling_interval, this means that the amount
#                          of time of allowed total path failure will be
#                          longer, since the tolerance time is
#                          (no_path_retry * polling_interval) seconds.
#                          SHOULD NOT BE USED WITH .features..
#
#    rr_min_io           : The number of IOs to route to a path before switching
#                          to the next path in the same path group
#
#    path_checker        : The default 'readsector0' path checker uses SCSI
#                          READ (opcode 0x28) which doesn't work in clustered
#                          environments. TUR (Test Unit Ready) does work in
#                          clustered environments with storage that subscribes
#                          to the SCSI-3 spec.
#
#    user_friendly_names : With this value set to .yes., DM MPIO devices will
#                          be named as .mpath0., .mpath1., .mpath2., etc. ...
#                          The /var/lib/mulitpath/bindings file is
#                          automatically generated, mapping the .mpathX. name
#                          to the wwid of the LUN. If set to "no", use the
#                          WWID as the alias. In either case this be will be
#                          overriden by any specific aliases in this file.
#
#
defaults {
    polling_interval    30
    failback            immediate
    no_path_retry       5
    rr_min_io           100
    path_checker        tur
    user_friendly_names yes 
}

#
# An example of blacklisting a local SCSI disk.
# Here a local disk with wwid SIBM-ESXSMAN3184MC_FUFR9P29044K2 is 
# blacklisted and will not appear when "multipath -l(l)" is invoked.
#
#
#blacklist {
#    wwid SIBM-ESXSMAN3184MC_FUFR9P29044K2
#}

#
# An example of using an alias. 
# NOTE: this will override the "user_friendly_name" for this LUN.
#
# Here a LUN from IBM storage with wwid 3600507630efffe32000000000000120a
# is given an alias of "IBM-1750" and will appear as "IBM-1750 
#(3600507630efffe32000000000000120a)", when "multipath -l(l)" is invoked.
#
#
#multipaths {
#    multipath {
#        wwid 3600507630efffe32000000000000120a
#        alias IBM-1750
#    }
#}

#
#  devices    : List of per storage controler settings, overrides default 
#              settings (device_maps block), overriden by per multipath 
#              settings (multipaths block)
#
#  vendor     : Vendor Name
#
#  product    : Product Name
#
#  path_grouping_policy : Path grouping policy to apply to multipath hosted
#                         by this storage controller
#
#  prio_callout : The program and args to callout to obtain a path 
#              weight. Weights are summed for each path group to
#              determine the next PG to use case of failure.
#              NOTE: If no callout then all paths have equals weight.
#
#
devices {
# These are the default settings for 2145 (IBM SAN Volume Controller)
    device {
        vendor                   "IBM"
        product                  "2145"
        path_grouping_policy     group_by_prio
        prio                     "alua"
    }

# These are the default settings for 1750 (IBM DS6000)

    device {
        vendor                   "IBM"
        product                  "1750500"
        path_grouping_policy     group_by_prio
        prio                     "alua"
    }

# These are the default settings for 2107 (IBM DS8000)
# Uncomment them if needed on this system
    device {
        vendor                   "IBM"
        product                  "2107900"
        path_grouping_policy     group_by_serial
    }

# These are the default settings for 2105 (IBM ESS Model 800)
    device {
        vendor                   "IBM"
        product                  "2105800"
        path_grouping_policy     group_by_serial
    }
}