metasync(1M) System Administration Commands metasync(1M)NAMEmetasync - handle metadevice resync during reboot
SYNOPSIS
/usr/sbin/metasync -h
/usr/sbin/metasync [-s setname] [buffer_size] metadevice
/usr/sbin/metasync [-s setname] -r [buffer_size]
/usr/sbin/metasync -p metadevice
/usr/sbin/metasync -c metadevice
DESCRIPTION
The metasync command starts a resync operation on the specified metade‐
vice. All components that need to be resynced are resynced. If the sys‐
tem crashes during a RAID5 initialization, or during a RAID5 resync,
either an initialization or resync restarts when the system reboots.
Applications are free to access a metadevice at the same time that it
is being resynced by metasync. Also, metasync performs the copy opera‐
tions from inside the kernel, which makes the utility more efficient.
Use the -r option in boot scripts to resync all possible submirrors.
OPTIONS
The following options are supported:
-c metadevice Cancels the resync that is in progress on the speci‐
fied metadevice. The resync will be stopped at its
current point and can be resumed by running the "meta‐
sync metadevice" command. This option only applies to
RAID1 volumes.
-h Displays usage message.
-p metadevice Regenerates parity information for RAID5 metadevices.
-s setname Specifies the name of the diskset on which metasync
will work. Using the -s option will cause the command
to perform its administrative function within the
specified diskset. Without this option, the command
will perform its function on local metadevices.
-r Specifies that the metasync command handle special
resync requirements during a system reboot. metasync-r should only be invoked from the svc:/system/mdmoni‐
tor service. The metasync command only resyncs those
metadevices that need to be resynced. metasync sched‐
ules all the mirror resyncs according to their pass
numbers.
To override the default buffer_size value used by the
svc:/system/mdmonitor service, you can edit /etc/sys‐
tem to specify:
set md_mirror:md_resync_bufsz = 2048
so that resyncs occur as quickly as possible.
OPERANDS
buffer_size Specifies the size (number of 512-byte disk blocks) of
the internal copy buffer for the mirror resync. The size
defaults to 1024 512-byte disk blocks. It can be no more
than 2048 blocks. For best performance (quickest comple‐
tion of the resync), 2048 blocks is the recommended
size.
EXIT STATUS
The following exit values are returned:
0 Successful completion.
>0 An error occurred.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Availability │storage/svm │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOmdmonitord(1M), metaclear(1M), metadb(1M), metadetach(1M), metahs(1M),
metainit(1M), metaoffline(1M), metaonline(1M), metaparam(1M), metare‐
cover(1M), metarename(1M), metareplace(1M), metaroot(1M), metaset(1M),
metassist(1M), metastat(1M), metattach(1M), md.tab(4), md.cf(4),
mddb.cf(4), md.tab(4), attributes(5), md(7D)NOTES
The metasync service is managed by the service management facility,
smf(5), under the service identifier:
svc:/system/mdmonitor
Administrative actions on this service, such as enabling, disabling, or
requesting restart, can be performed using svcadm(1M). The service's
status can be queried using the svcs(1) command.
SunOS 5.11 27 Mar 2006 metasync(1M)
