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32 .Nd "control utility for RAID3 devices"
38 .Ar prov prov prov ...
78 utility is used for RAID3 array configuration.
79 After a device is created, all components are detected and configured
81 All operations such as failure detection, stale component detection, rebuild
82 of stale components, etc.\& are also done automatically.
85 utility uses on-disk metadata (the provider's last sector) to store all needed
90 indicates an action to be performed:
91 .Bl -tag -width ".Cm configure"
93 Create a RAID3 device.
94 The last given component will contain parity data, whilst the others
95 will all contain regular data.
96 The number of components must be equal to 3, 5, 9, 17, etc.\& (2^n + 1).
98 Additional options include:
99 .Bl -tag -width ".Fl h"
101 Hardcode providers' names in metadata.
103 Turn off autosynchronization of stale components.
105 Use parity component for reading in round-robin fashion.
106 Without this option the parity component is not used at all for reading operations
107 when the device is in a complete state.
108 With this option specified random I/O read operations are even 40% faster,
109 but sequential reads are slower.
110 One cannot use this option if the
112 option is also specified.
114 Use verify reading feature.
115 When reading from a device in a complete state, also read data from the parity component
116 and verify the data by comparing XORed regular data with parity data.
117 If verification fails, an
119 error is returned and the value of the
120 .Va kern.geom.raid3.stat.parity_mismatch
122 One cannot use this option if the
124 option is also specified.
127 Clear metadata on the given providers.
129 Configure the given device.
131 Additional options include:
132 .Bl -tag -width ".Fl a"
134 Turn on autosynchronization of stale components.
136 Do not hardcode providers' names in metadata.
138 Hardcode providers' names in metadata.
140 Turn off autosynchronization of stale components.
142 Turn on round-robin reading.
144 Turn off round-robin reading.
146 Turn on verify reading.
148 Turn off verify reading.
151 Rebuild the given component forcibly.
152 If autosynchronization was not turned off for the given device, this command
153 should be unnecessary.
155 Add the given component to the existing array, if one of the components was
156 removed previously with the
158 command or if one component is missing and will not be connected again.
160 Additional options include:
161 .Bl -tag -width ".Fl h"
163 Hardcode providers' names in metadata.
166 Remove the given component from the given array and clear metadata on it.
168 Stop the given arrays.
170 Additional options include:
171 .Bl -tag -width ".Fl f"
173 Stop the given array even if it is opened.
189 Additional options include:
190 .Bl -tag -width ".Fl v"
195 Exit status is 0 on success, and 1 if the command fails.
197 Use 3 disks to setup a RAID3 array (with the round-robin reading feature).
198 Create a file system, mount it, then unmount it and stop device:
199 .Bd -literal -offset indent
200 graid3 label -v -r data da0 da1 da2
201 newfs /dev/raid3/data
202 mount /dev/raid3/data /mnt
210 Create a RAID3 array, but do not use the automatic synchronization feature.
211 Rebuild parity component:
212 .Bd -literal -offset indent
213 graid3 label -n data da0 da1 da2
214 graid3 rebuild data da2
217 Replace one data disk with a brand new one:
218 .Bd -literal -offset indent
219 graid3 remove -n 0 data
220 graid3 insert -n 0 data da5
235 .An Pawel Jakub Dawidek Aq pjd@FreeBSD.org
237 There should be a section with an implementation description.
239 Documentation for sysctls
240 .Va kern.geom.raid3.*