XLV Daemons

XLV Daemons

The XLV daemons are:

xlv_labd: xlv_labd updates logical volume labels. It is started automatically at system startup if it is installed and there are active XLV logical volumes.
xlvd: xlvd handles I/O to plexes and performs plex error recovery. It is created automatically during system startup if plexing software is installed and there are active XLV logical volumes.
xlv_plexd: xlv_plexd is responsible for making all plexes within a subvolume have the same data. It is started automatically at system startup if there are active XLV logical volumes.

XLV does not require an explicit configuration file, nor is it turned on and off with the chkconfig command. XLV is able to assemble logical volumes based solely upon information written in the logical volume labels. During initialization, the system performs a hardware inventory, reads all the logical volume labels, and automatically assembles the available disks into previously defined volumes.

If some disks are missing, XLV checks to see if there are enough volume elements among the available plexes to map the entire address space. If the whole address space is available, XLV brings the volume online even if some of the plexes are incomplete.