The Logical Volume Manager (LVM) in AIX is incapable of switching between multiple paths that may exist to the boot disk. If the path that LVM selects becomes unavailable at boot time, the
root file system is disabled, and the boot fails. DMP can be configured to overcome this problem by ensuring that an alternate path is available at boot time.
Support for LVM bootability over DMP is enabled by running the following command:
Individual DMP nodes or subpaths can be added or removed from those supported by using the
vxdmproot command with the
remove keywords, and specifying a DMP node name or operating system native device name as an argument, for example:
/usr/sbin/vxdmproot add hdisk0
Support for LVM bootability over DMP is disabled by running the following command:
LVM bootability over DMP can be verified as being enabled on a system if the following commands show the same major number for the DMP driver and for the boot disk:
ls -l /dev/vx/dmpconfig
ls -l /dev/`bootinfo -b`
vxdmproot(1M) manual page.