metasync(1m) [sunos man page]
metasync(1M) System Administration Commands metasync(1M) NAME
metasync - 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 DESCRIPTION
The metasync command starts a resync operation on the specified metadevice. All components that need to be resynced are resynced. If the system 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 oper- ations 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: -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/mdmonitor service. The metasync command only resyncs those metadevices that need to be resynced. metasync schedules 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/system 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 128 512-byte disk blocks (64 Kbytes). It can be no more than 2048 blocks. For best performance (quick- est completion 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 |SUNWmdu | +-----------------------------+-----------------------------+ SEE ALSO
mdmonitord(1M), metaclear(1M), metadb(1M), metadetach(1M), metahs(1M), metainit(1M), metaoffline(1M), metaonline(1M), metaparam(1M), metarecover(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) Solaris Volume Manager Administration Guide 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 ser- vice's status can be queried using the svcs(1) command. SunOS 5.10 24 Nov 2004 metasync(1M)
Check Out this Related Man Page
metaoffline(1M) System Administration Commands metaoffline(1M) NAME
metaoffline, metaonline - place submirrors offline and online SYNOPSIS
/usr/sbin/metaoffline -h /usr/sbin/metaoffline [-s setname] [-f] mirror submirror /usr/sbin/metaonline -h /usr/sbin/metaonline [-s setname] mirror submirror DESCRIPTION
The metaoffline command prevents Solaris Volume Manager from reading and writing to the submirror that has been taken offline. While the submirror is offline, all writes to the mirror will be kept track of (by region) and will be written when the submirror is brought back online. The metaoffline command can also be used to perform online backups: one submirror is taken offline and backed up while the mirror remains accessible. (However, if this is a two-way mirror, data redundancy is lost while one submirror is offline.) The metaoffline command differs from the metadetach command because it does not sever the logical association between the submirror and the mirror. To completely remove a submirror from a mirror, use the metadetach command. A submirror that has been taken offline will only remain offline until the metaonline command is invoked or the system is rebooted. When the metaonline command is used, reading from and writing to the submirror resumes. A resync is automatically invoked to resync the regions written while the submirror was offline. Writes are directed to the submirror during resync. Reads, however, will come from a dif- ferent submirror. Once the resync operation completes, reads and writes are performed on that submirror. The metaonline command is only effective on a submirror of a mirror that has been taken offline. The metaoffline and metaonline commands can not be used on RAID 1 volumes in application-based recovery (ABR) mode. A submirror that has been taken offline with the metaoffline command can only be mounted as read-only. OPTIONS
Root privileges are required for all of the following options except -h. -f Forces offlining of submirrors that have slices requiring maintenance. -h Displays usage message. -s setname Specifies the name of the diskset on which metaoffline and metaonline will work. Using the -s option will cause the com- mand to perform its administrative function within the specified diskset. Without this option, the command will perform its function on local metadevices. mirror Specifies the metadevice name of the mirror from which the submirror will be either taken offline or put online. submirror Specifies the metadevice name of the submirror to be either taken offline or put online. EXAMPLES
Example 1: Taking a Submirror Offline This example takes one submirror, d9, offline from mirror d10. # metaoffline d10 d9 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 |SUNWmdu | +-----------------------------+-----------------------------+ SEE ALSO
mdmonitord(1M), metaclear(1M), metadb(1M), metadetach(1M), metahs(1M), metainit(1M), metaparam(1M), metarecover(1M), metarename(1M), metareplace(1M), metaroot(1M), metaset(1M), metassist(1M), metastat(1M), metasync(1M), metattach(1M), md.tab(4), md.cf(4), mddb.cf(4), md.tab(4), attributes(5), md(7D) Solaris Volume Manager Administration Guide NOTES
The metaonline and metaoffline commands are not applicable to mirrors in application-based recovery (ABR) mode. SunOS 5.10 12 Apr 2004 metaoffline(1M)