freebsd man page for hastctl

HASTCTL(8)						    BSD System Manager's Manual 						HASTCTL(8)

NAME
     hastctl -- Highly Available Storage control utility

SYNOPSIS
     hastctl create [-d] [-c config] [-e extentsize] [-k keepdirty] [-m mediasize] name ...
     hastctl role [-d] [-c config] <init | primary | secondary> all | name ...
     hastctl list [-d] [-c config] [all | name ...]
     hastctl status [-d] [-c config] [all | name ...]
     hastctl dump [-d] [-c config] [all | name ...]

DESCRIPTION
     The hastctl utility is used to control the behaviour of the hastd(8) daemon.

     This utility should be used by HA software like heartbeat or ucarp to setup HAST resources role when changing from primary mode to secondary
     or vice versa.  Be aware that if a file system like UFS exists on HAST provider and primary node dies, file system has to be checked for
     inconsistencies with the fsck(8) utility after switching secondary node to primary role.

     The first argument to hastctl indicates an action to be performed:

     create  Initialize local provider configured for the given resource.  Additional options include:

	     -e extentsize  Size of an extent.	Extent is a block which is used for synchronization.  hastd(8) maintains a map of dirty extents
			    and extent is the smallest region that can be marked as dirty.  If any part of an extent is modified, entire extent
			    will be synchronized when nodes connect.  If extent size is too small, there will be too much disk activity related to
			    dirty map updates, which will degrade performance of the given resource.  If extent size is too large, synchroniza-
			    tion, even in case of short outage, can take a long time increasing the risk of losing up-to-date node before synchro-
			    nization process is completed.  The default extent size is 2MB.

	     -k keepdirty   Maximum number of dirty extents to keep dirty all the time.  Most recently used extents are kept dirty to reduce num-
			    ber of metadata updates.  The default number of most recently used extents which will be kept dirty is 64.

	     -m mediasize   Size of the smaller provider used as backend storage on both nodes.  This option can be omitted if node providers have
			    the same size on both sides.

	     If size is suffixed with a k, M, G or T, it is taken as a kilobyte, megabyte, gigabyte or terabyte measurement respectively.

     role    Change role of the given resource.  The role can be one of:

	     init	Resource is turned off.

	     primary	Local hastd(8) daemon will act as primary node for the given resource.	System on which resource role is set to primary
			can use /dev/hast/<name> GEOM provider.

	     secondary	Local hastd(8) daemon will act as secondary node for the given resource - it will wait for connection from the primary
			node and will handle I/O requests received from it.  GEOM provider /dev/hast/<name> will not be created on secondary node.

     list    Present verbose status of the configured resources.

     status  Present terse (and more easy machine-parseable) status of the configured resources.

     dump    Dump metadata stored on local component for the configured resources.

     In addition, every subcommand can be followed by the following options:

     -c config	Specify alternative location of the configuration file.  The default location is /etc/hast.conf.

     -d 	Print debugging information.  This option can be specified multiple times to raise the verbosity level.

FILES
     /etc/hast.conf    Configuration file for hastctl and hastd(8).
     /var/run/hastctl  Control socket used by hastctl to communicate with the hastd(8) daemon.

EXIT STATUS
     Exit status is 0 on success, or one of the values described in sysexits(3) on failure.

EXAMPLES
     Initialize HAST provider, create file system on it and mount it.

	   nodeB# hastctl create shared
	   nodeB# hastd
	   nodeB# hastctl role secondary shared

	   nodeA# hastctl create shared
	   nodeA# hastd
	   nodeA# hastctl role primary shared
	   nodeA# newfs -U /dev/hast/shared
	   nodeA# mount -o noatime /dev/hast/shared /shared
	   nodeA# application_start

     Switch roles for the shared HAST resource.

	   nodeA# application_stop
	   nodeA# umount -f /shared
	   nodeA# hastctl role secondary shared

	   nodeB# hastctl role primary shared
	   nodeB# fsck -t ufs /dev/hast/shared
	   nodeB# mount -o noatime /dev/hast/shared /shared
	   nodeB# application_start

SEE ALSO
     sysexits(3), geom(4), hast.conf(5), fsck(8), ggatec(8), ggatel(8), hastd(8), mount(8), newfs(8)

AUTHORS
     The hastctl was developed by Pawel Jakub Dawidek <pjd@FreeBSD.org> under sponsorship of the FreeBSD Foundation.

BSD
								  March 14, 2013							       BSD