1metasync(1M) System Administration Commands metasync(1M)
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6 metasync - handle metadevice resync during reboot
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9 /usr/sbin/metasync -h
10 /usr/sbin/metasync [-s setname] [buffer_size] metadevice
13 /usr/sbin/metasync [-s setname] -r [buffer_size]
16 /usr/sbin/metasync -p metadevice
19 /usr/sbin/metasync -c metadevice
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25 The metasync command starts a resync operation on the specified metade‐
26 vice. All components that need to be resynced are resynced. If the sys‐
27 tem crashes during a RAID5 initialization, or during a RAID5 resync,
28 either an initialization or resync restarts when the system reboots.
29 Applications are free to access a metadevice at the same time that it
32 is being resynced by metasync. Also, metasync performs the copy opera‐
33 tions from inside the kernel, which makes the utility more efficient.
34 Use the -r option in boot scripts to resync all possible submirrors.
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39 The following options are supported:
40 -c metadevice Cancels the resync that is in progress on the speci‐
42 fied metadevice. The resync will be stopped at its
43 current point and can be resumed by running the "meta‐
44 sync metadevice" command. This option only applies to
45 RAID1 volumes.
46 -h Displays usage message.
49 -p metadevice Regenerates parity information for RAID5 metadevices.
52 -s setname Specifies the name of the diskset on which metasync
55 will work. Using the -s option will cause the command
56 to perform its administrative function within the
57 specified diskset. Without this option, the command
58 will perform its function on local metadevices.
59 -r Specifies that the metasync command handle special
62 resync requirements during a system reboot. metasync
63 -r should only be invoked from the svc:/system/mdmoni‐
64 tor service. The metasync command only resyncs those
65 metadevices that need to be resynced. metasync sched‐
66 ules all the mirror resyncs according to their pass
67 numbers.
68 To override the default buffer_size value used by the
70 svc:/system/mdmonitor service, you can edit /etc/sys‐
71 tem to specify:
72 set md_mirror:md_resync_bufsz = 2048
74 so that resyncs occur as quickly as possible.
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80 buffer_size Specifies the size (number of 512-byte disk blocks) of
81 the internal copy buffer for the mirror resync. The size
82 defaults to 1024 512-byte disk blocks. It can be no more
83 than 2048 blocks. For best performance (quickest comple‐
84 tion of the resync), 2048 blocks is the recommended
85 size.
86
89 The following exit values are returned:
90 0 Successful completion.
92 >0 An error occurred.
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98 See attributes(5) for descriptions of the following attributes:
99 ┌─────────────────────────────┬─────────────────────────────┐
104 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
105 ├─────────────────────────────┼─────────────────────────────┤
106 │Availability │SUNWmdu │
107 └─────────────────────────────┴─────────────────────────────┘
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110 mdmonitord(1M), metaclear(1M), metadb(1M), metadetach(1M), metahs(1M),
111 metainit(1M), metaoffline(1M), metaonline(1M), metaparam(1M), metare‐
112 cover(1M), metarename(1M), metareplace(1M), metaroot(1M), metaset(1M),
113 metassist(1M), metastat(1M), metattach(1M), md.tab(4), md.cf(4),
114 mddb.cf(4), md.tab(4), attributes(5), md(7D)
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120 The metasync service is managed by the service management facility,
121 smf(5), under the service identifier:
122 svc:/system/mdmonitor
124 Administrative actions on this service, such as enabling, disabling, or
129 requesting restart, can be performed using svcadm(1M). The service's
130 status can be queried using the svcs(1) command.
131SunOS 5.11 27 Mar 2006 metasync(1M)