1.3. DM-Multipath Components

1.3. DM-Multipath Components

Table 1.1, “DM-Multipath Components”. describes the components of DM-Multipath.

Component Description
dm-multipath kernel module Reroutes I/O and supports failover for paths and path groups.
multipath command Lists and configures multipath devices. Normally started up with /etc/rc.sysinit, it can also be started up by a udev program whenever a block device is added or it can be run by the initramfs file system.
multipathd daemon Monitors paths; as paths fail and come back, it may initiate path group switches. Provides for interactive changes to multipath devices. This must be restarted for any changes to the /etc/multipath.conf file.
kpartx command Creates device mapper devices for the partitions on a device It is necessary to use this command for DOS-based partitions with DM-MP. The kpartx is provided in its own package, but the device-mapper-multipath package depends on it.
Table 1.1. DM-Multipath Components


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