Installation guide

flush_on_last_del (RHEL 4.7 and later) If set to yes, the m ultipathd daemon will
disable queueing when the last path to a device has been deleted.
The default value is no.
mode (RHEL 4.7 and later) The mode to use for the multipath device
nodes, in octal. The default value is determined by the process.
uid (RHEL 4.7 and later) The user ID to use for the multipath device
nodes. You must use the numeric user ID. T he default value is
determined by the process.
gid (RHEL 4.7 and later) The group ID to use for the multipath device
nodes. You must use the numeric group ID. T he default value is
determined by the process.
The following example shows multipath attributes specified in the configuration file for two specific
multipath devices. The first device has a WWID of 3600508b4 000156d70001200000b0000 and a
symbolic name of yellow.
The second multipath device in the example has a WWID of 1DEC_____3218167584 74 and a
symbolic name of red. In this example, the rr_weight attributes is set to priorities.
multipaths {
multipath {
wwid 3600508b4000156d70001200000b0000
alias yellow
path_grouping_policy multibus
path_checker readsector0
path_selector "round-robin 0"
failback m anual
rr_weight priorities
no_path_retry 5
}
multipath {
wwid 1DEC_____321816758474
alias red
rr_weight priorities
}
}
4.5. Configuration File Devices
Table 4.3, “Device Attributes” shows the attributes that you can set for each individual storage device in
the devices section of the m ultipath.conf configuration file. These attributes are used by DM-
Multipath unless they are overwritten by the attributes specified in the m ultipaths section of the
m ultipath.conf file for paths that contain the device. These attributes override the attributes set in
the defaults section of the m ultipath.conf file.
Many devices that support multipathing are included by default in a multipath configuration. T he values
for the devices that are supported by default are listed in the m ultipath.conf.defaults file. You
probably will not need to modify the values for these devices, but if you do you can overwrite the default
values by including an entry in the the configuration file for the device that overwrites those values. You
can copy the device configuration defaults from the m ultipath.conf.defaults file for the device
and override the values that you want to change.
To add a device to this section of the configuration file that is not configured automatically by default, you
Red Hat Enterprise Linux 4 DM Multipath
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