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mkraid(8) [redhat man page]

mkraid(8)						      System Manager's Manual							 mkraid(8)

mkraid - initializes/upgrades RAID device arrays SYNOPSIS
mkraid [--configfile] [--version] [--force] [--upgrade] [-cvfu] </dev/md?>+ DESCRIPTION
mkraid sets up a set of block devices into a single RAID array. It looks in its configuration file for the md devices mentioned on the command line, and initializes those arrays. mkraid works for all types of RAID arrays (RAID1, RAID4, RAID5, LINEAR and RAID0). Note that initializing RAID devices destroys all of the data on the consituent devices. OPTIONS
-c, --configfile filename Use filename as the configuration file (/etc/raidtab is used by default). -f, --force Initialize the consituent devices, even if they appear to have data on them already. -h, --help Displays a short usage message, then exits. -o, --upgrade This option upgrades older arrays to the current kernel's RAID version, without destroying data. Although the utility detects vari- ous pitfalls like mixed up disks and inconsistent superblocks, this option should be used with care. -V, --version Displays a short version message, then exits. NOTES
The raidtools are derived from the md-tools and raidtools packages, which were originally written by Marc Zyngier, Miguel de Icaza, Gadi Oxman, Bradley Ward Allen, and Ingo Molnar. BUGS
Probably many. SEE ALSO
raidtab(5), raidstart(8), raid0run(8), raidstop(8) mkraid(8)

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LSRAID(8)							Linus md Utilities							 LSRAID(8)

lsraid - List and query Linux md devices. SYNOPSIS
lsraid -A [-g|-s|-f] {-a <device> | -d <device>} ... lsraid -A -p lsraid -D [-l] {-a <device> | -d <device>} ... lsraid -D -p lsraid -R {-a <device> | -d <device>} ... lsraid -R -p lsraid -h lsraid -V DESCRIPTION
lsraid is a program for querying Linux md devices. It can describe the composite device and the block devices that belong to it. It can also provide a description of the md device suitable for including in the /etc/raidtab configuration file. lsraid also has the ability to operate on online and offline devices. It can read an online device via the kernel interface and provide information about it. When a device is offline, lsraid can look at any of the block devices that are a part of the md device and read the persistent md superblock for information. OPTIONS
-A Selects array-based operation. lsraid will query the given devices and output a short listing of the referenced md devices. -a <device> Adds md device <device> to the list of devices to query. If the device is online, lsraid will discover all of the block devices that belong to it via the kernel interface. Otherwise lsraid will only be able to verify that the device exists. -D Selects disk-based operation. lsraid will query the given devices and then output a description of all the member disks requested. -d <device> Adds block device <device> to the list of devices to query. lsraid will read the md superblock off of <device> and use it to discover the assocated md device and block devices. -f Displays only failed block devices in array-based mode (-A). -g Displays only good block devices in array-based mode (-A). -h, --help Displays a short usage message, then exits. -l Displays a long dump of block device superblocks in disk-based mode (-D). This output is verbatim from the on-disk md superblock, and reflects the state on the specific disk, not the state the md device currently considers authorative. -p Scans all block devices in /proc/partitions for RAID arrays. This can be slow in the presence of network block devices and the like. This option is mutually exclusive with the -a and -d options. -R Selects raidtab operation. lsraid will query all the devices specified and output a description of the referenced md devices in a for- mat suitable for placing in a raidtab(5) file. -s Displays only spare block devices in array-based mode (-A). NOTES
lsraid cannot discover the block devices that make up an offline md device. Providing one of the member devices with the -d option allows lsraid to discover the rest of the information about the offline md device. Disk-based operation only displays the block devices specified on the command line. Specify the md device on the command line to see information about all of the member disks. If the md device is offline, specify both the md device and one of the member disks. lsraid does not do any special handling of md devices composed of other md devices (eg RAID 1+0). The member devices are merely treated as block devices while in the context of the parent device. This is only an issue for raidtab-based operation. The raidtab(5) output will be printed in the order the md devices are queried. This means that a command creating a raidtab(5) for a RAID 1+0 device should list the member devices first on the command line. EXAMPLES
lsraid -A -a /dev/md0 Display a short listing of the md0 device. lsraid -A -d /dev/sda1 Display a short listing of the array that sda1 belongs to. lsraid -A -f -a /dev/md0 Display the failed devices belonging to the md0 device. lsraid -D -l -a /dev/md0 Display a long dump of the on-disk md superblock of every disk in md0. lsraid -D -a /dev/md0 -d /dev/sda1 Display a short discription of the disks in md0 as well as a short description of the disk sda1. sda1 will only be described once if it belongs to md0. lsraid -R -a /dev/md0 -a /dev/md1 -a /dev/md2 Display a description of the arrays in an output format suitable for using in raidtab(5) files. Note that if md0 and md1 are raid0 arrays and md2 is a raid1 created from md0 and md1, this command will output the information in the correct order. lsraid -R -p Scan all block devices in /proc/partitions and display all discovered md devices in a format suitable for using in raidtab(5) files. BUGS
Probably. SEE ALSO
mkraid(8), raidtab(5), raidstart(8), raidstop(8) VERSION
lsraid version 0.7.0 (26 March 2002) HISTORY
Version 0.7.0 Added scanning of active block device partitions. Version 0.4.0 Initial documented version. Functionally complete. AUTHOR
Joel Becker <> COPYRIGHT
Copyright (C) Oracle Corporation, Joel Becker. All rights reserved. This program is free software; see the file COPYING in the source distribution for the terms under which it can be redistributed and/or modified. 3rd Berkeley Distribution 2002-03-26 LSRAID(8)

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