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 speci-
     fied  metadevice.   All  components that need to be resynced
     are resynced. If the system crashes during a RAID5 initiali-
     zation,  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 operations 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 administra-
                     tive  function within the specified diskset.
                     Without this option, the command  will  per-
                     form 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 metadev-
                     ices  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  possi-
                     ble.



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 (quickest 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  attri-
     butes:

     ____________________________________________________________
    |       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 service's status can be queried  using  the
     svcs(1) command.