Emerson ATCA-S201 manual Software RAID, CLI command syntax

RTM-ATCA-SXXX Overview

md0 ˇ

Submit

Ignore Warnings

Import Foreign Array

Clear ownership

Use this drop down menu to choose a volume name. Four choices: md0, md1,md2 or md3 Click to commit the selections and create the new RAID device.

‘Radio button’ will ignore minor mdadm warnings. Example ignore warning when creating RAID1 with disks that have greater than 1% capacity difference. This Filed self-clears on each use.

Will display ONLY in situations when a drive contains meta-data that indicates it was at one time a member of a software RAID volume. Click and select participating drives to attempt an import of the volume.

Will display ONLY in situations when a drive contains meta-data that indicates it was at one time a member of a software RAID volume. Click and select drives to clear all meta-data stored on these disk(s). This operation will permanently eliminate the import array option.

Important considerations and volume restrictions

5.A maximum of 4 software-RAID volumes may be defined on each ATCA-S201.

6.The default stripe size is 64KB, but can be changed by creating the array using the CLI mdadm tool instead.

7.A user may assign multiple spare disks to each volume.

5.3.2Software RAID, CLI command syntax

Table 27 CLI command syntax, mdadm: manage RAID configuration

Create new volumemdadm –-create raiddevice –n <#devices> -l <raidlevel> [-c <stripe_size>] <component-devices>

--create	“Create” mode, used initialize a new md array, associate some devices with it,
	and activate the array.
Raiddevice	Device name assigned to new volume. Example /dev/md0.
<#devices>	Integer, specifies the number of <component-devices>
<raidlevel>	Integer: 4=raid4, 5=raid5, 6=raid6
<stripe_size>	Optional, will default to 64 if omitted, expressed in kilobytes. Within a stripe,
	this defines the ‘chunk’ of data read or written to any single member disk.
<component-devices>	Space delimited list of component devices. Example /dev/sda /dev/sdb…
Preserve new volume	mdadm --detail --scan > /etc/mdadm.conf
attributes
	Issue this command immediately after creating a new volume. This command
	preserves key volume parameters, and ensures the new volume is available
	across system reboots.
List volume status	mdadm --detail --scan
	Issue this command at any time to inspect volume status
Create hot spare	mdadm –-add raiddevice <spare-device>
--add	Used to add a spare disk to an existing raid-device. Users may issue this
	commend any number of times to specify multiple spare drives if available.
Raiddevice	Device name assigned to existing volume. Example /dev/md0
<spare-device>	Designate spare device. Example /dev/sda
Remove faulty disk	mdadm –-remove raiddevice <faulty-device>

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