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HASTCTL(8) FreeBSD 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, synchronization,
even in case of short outage, can take a long
time increasing the risk of losing up-to-date
node before synchronization 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 number 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.
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),
sponsorship of the FreeBSD Foundation.
FreeBSD 14.2-RELEASE September 8, 2016 FreeBSD 14.2-RELEASE