Multipaths Device Configuration Attributes - Red Hat CLUSTER SUITE 4.7 DM MULTIPATH Configuration And Administration Manual

Attribute
rr_min_io
rr_weight
failback
no_path_retry
user_friendly_names
bindings_file
Table 4.1. Multipath Configuration Defaults

4.4. Multipaths Device Configuration Attributes

Table 4.2, "Multipath Attributes"
the multipath.conf configuration file for each specific multipath device. These attributes apply only
to the one specified multipath. These defaults are used by DM-Multipath and override attributes set in
the defaults and devices sections of the multipath.conf file.
Description
Specifies the number of I/O requests to route to a path before
switching to the next path in the current path group. The default
value is 1000.
If set to priorities, then instead of sending rr_min_io
requests to a path before calling selector to choose the
next path, the number of requests to send is determined by
rr_min_io times the path's priority, as determined by the
prio_callout program. Currently, there are priority callouts only
for devices that use the group_by_prio path grouping policy,
which means that all the paths in a path group will always have the
same priority.
If set to uniform, all path weights are equal. The default value is
uniform.
Specifies path group failback.
A value of 0 or immediate specifies that as soon as there is a
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 manual specifies that failback can happen only with
operator intervention.
The default value is manual.
A numeric value for this attribute specifies the number of times
the system should attempt to use a failed path before disabling
queueing.
A value of fail indicates immediate failure, without queuing.
A value of queue indicates that queuing should not stop until the
path is fixed.
The default value is (null).
If set to yes, specifies that the system should using the bindings
file /var/lib/multipath/bindings to assign a persistent
and unique alias to the multipath, in the form of mpathn. If set to
no, specifies that the system should use use the WWID as the
alias for the multipath. In either case, what is specified here will
be overriden by any device-specific aliases you specify in the
multipaths section of the configuration file. The default value is
no.
The location of the bindings file that is used with the
user_friendly_names option. The default value is /var/lib/
multipath/bindings.
shows the attributes that you can set in the multipaths section of
Multipaths Device Configuration Attributes
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