Red Hat DEVICE-MAPPER MULTIPATH 5.2 Configuration And Administration Manual page 36

Chapter 4. The DM-Multipath Configuration File
device for multipath.
Attribute
vendor
product
product_blacklist
path_grouping_policy
getuid_callout
prio_callout
path_checker
path_selector
failback
features
hardware_handler
26
Description
Specifies the vendor name of the storage device to which the
attributes apply, for example
device
Specifies the product name of the storage device to which the
attributes apply, for example
device
Specifies a regular expression used to blacklist devices by
product.
Specifies the default path grouping policy to apply to
unspecified multipaths. Possible values include:
= 1 path per priority group
failover
= all valid paths in 1 priority group
multibus
= 1 priority group per detected serial
group_by_serial
number
= 1 priority group per path priority value
group_by_prio
group_by_node_name
Specifies the default program and arguments to call out to
obtain a unique path identifier. An absolute path is required.
Specifies the the default program and arguments to call out to
obtain a path weight. Weights are summed for each path
group to determine the next path group to use in case of
failue. "none" is a valid value.
Specifies the default method used to determine the state of
the paths. Possible values include
,
emc_clariion hp_sw
Specifies the default algorithm to use in determining what
path to use for the next I/O operation.
Specifies path group failback.
A value of 0 or
immediate
path group whith a higher priority than the current path group
the system switches to that path group.
A numeric value greater than zero specifies deferred failback,
expressed in seconds.
A value of specifies that failback can happen only with
manual
operator intervention.
The extra features of multipath devices. The only existing
feature is
queue_if_no_path
to
no_path_retry queue
Specifies a module that will be used to perform hardware
specific actions when switching path groups or handling I/O
errors. Possible values include
COMPAQ
HSV110 (C)COMPAQ
= 1 priority group per target node name
readsector0
, and .
directio
specifies that as soon as there is a
, which is the same as setting
.
, , and
0 1 emc
.
.
and ,
tur
. The
1 rdac