diff options
author | Peter Galbavy <peter@cvs.openbsd.org> | 1999-07-30 14:45:34 +0000 |
---|---|---|
committer | Peter Galbavy <peter@cvs.openbsd.org> | 1999-07-30 14:45:34 +0000 |
commit | 2d131282dabeb59997e716557431544d132defee (patch) | |
tree | 36b98c66a45bd7e085f283abb47dcf53504808af /share/man/man4/raid.4 | |
parent | aad8058264cfbb51ec169e8ecd7f04209b706634 (diff) |
Update RAIDframe from NetBSD-current as of 1999/07/26.
Please note that you *must* follow the upgrade instructions at
http://www.cs.usask.ca/staff/oster/clabel_upgrade.html
before installing the new raidctl and new kernel using this code.
Diffstat (limited to 'share/man/man4/raid.4')
-rw-r--r-- | share/man/man4/raid.4 | 34 |
1 files changed, 30 insertions, 4 deletions
diff --git a/share/man/man4/raid.4 b/share/man/man4/raid.4 index 98a977f5757..dc53004db6d 100644 --- a/share/man/man4/raid.4 +++ b/share/man/man4/raid.4 @@ -1,4 +1,5 @@ -.\" $OpenBSD: raid.4,v 1.6 1999/07/09 13:35:48 aaron Exp $ +.\" $OpenBSD: raid.4,v 1.7 1999/07/30 14:45:31 peter Exp $ +.\" $NetBSD: raid.4,v 1.5 1999/03/16 01:19:17 garbled Exp $ .\" .\" .\" Copyright (c) 1998 The NetBSD Foundation, Inc. @@ -108,16 +109,41 @@ reconstructed from the data and parity present on the other components. This results in much slower data accesses, but does mean that a failure need not bring the system to a complete halt. .Pp +The RAID driver supports and enforces the use of +.Sq component labels . +A +.Sq component label +contains important information about the component, including a +user-specified serial number, the row and column of that component in the RAID +set, and whether the data (and parity) on the component is +.Sq clean . +If the driver determines that the labels are very inconsistent with +respect to each other (e.g. two or more serial numbers do not match) +or that the component label is not consistent with it's assigned place +in the set (e.g. the component label claims the component should be +the 3rd one a 6-disk set, but the RAID set has it as the 3rd component +in a 5-disk set) then the device will fail to configure. If the +driver determines that exactly one component label seems to be +incorrect, and the RAID set is being configured as a set that supports +a single failure, then the RAID set will be allowed to configure, but +the incorrectly labeled component will be marked as +.Sq failed , +and the RAID set will begin operation in degraded mode. +If all of the components are consistent among themselves, the RAID set +will configure normally. +.Pp The driver supports .Sq hot spares , disks which are on-line, but are not actively used in an existing filesystem. Should a disk fail, the -driver is capable of reconstructing the failed disk onto a hot spare. +driver is capable of reconstructing the failed disk onto a hot spare +or back onto a replacment drive. If the components are hot swapable, the failed disk can then be removed, a new disk put in it's place, and a copyback operation performed. The copyback operation, as its name indicates, will copy the reconstructed data from the hot spare to the previously failed -(and now replaced) disk. +(and now replaced) disk. Hot spares can also be hot-added using +.Xr raidctl 8 . .Pp If a component cannot be detected when the RAID device is configured, that component will be simply marked as 'failed'. @@ -130,7 +156,7 @@ is For any of the RAID flavours which have parity data, .Xr raidctl 8 must be used with the -.Fl r +.Fl i option to re-write the data when either a) a new RAID device is brought up for the first time or b) after an un-clean shutdown of a RAID device. By performing this on-demand recomputation of all parity |