Red Hat DEVICE-MAPPER MULTIPATH 4.6, Configuration And Administration Manual

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}
2.2. Blacklisting By Device Name
You can blacklist device types by device name so that they will not be grouped into a multipath
device by specifying a
devnode
entry in the
devnode_blacklist
section of the configuration
file.
The following example shows the lines in the configuration file that would blacklist all SCSI
devices, since it blacklists are sd* devices.
devnode_blacklist {
devnode "^sd[a-z]"
}
You can use a
devnode
entry in the
blacklist
section of the configuraion file to specify
individual devices to blacklist rather than all devices of specific type; this is not recommended,
however. Unless it is statically mapped by
udev
rules, there is no guarantee that a specific
device will have the same name on reboot. For example, a device name could change from
/dev/sda
to
/dev/sdb
on reboot.
By default, the following
devnode
entries are compiled in the default blacklist; the devices that
these entires blacklist do not generally support DM-Multipath.
blacklist {
devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
devnode "^hd[a-z]"
devnode "^cciss!c[0-9]d[0-9]*"
}
3. Configuration File Defaults
The
/etc/multipath.conf
configuration file includes a
defaults
section that sets the
user_friendly_names
parameter to
yes
, as follows.
defaults {
user_friendly_names yes
}
This overwrites the default value of the
user_friendly_names
parameter.
The configuration file includes a template of configuration defaults. This section is commented
Blacklisting By Device Name
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