Linux and HW raid - an administrators summary

For RAID to be usefull in a enterprise environment, one needs to get a warning when a disk fails, and be able to replace this disk without having to reboot. This page is a summary of the status of some (most/all) hw raid drivers supported by the default linux kernel. The following criteria is being considered:

Summary of all known drivers

Driver name

Supported

Status

Cmd tool

GUI tool

Debian-installer

3w-xxxx

Yes

No

No

No

Yes

3w-9xxx

?

?

?

?

?

aacraid

Yes

No*

No*

?

?

cciss

Yes

No

?

?

No (Debian BTS #278887)

DAC960

Yes

Yes

?

?

Yes

dpt_i2o

Yes

?

Yes

?

?

gdth

Yes

Yes

No*

?

Yes

ips

Yes

No*

No*

No*

Yes

megaraid

Yes

?

?

?

?

megaraid_mbox

Yes

?

?

?

?

megaraid2

Yes

Yes

?

?

No

mptscsih

Yes

?

Yes

?

?

Details about individual drivers

3w-xxxx

Nothing known about 3w-xxxx.

Hardware using this driver:

3w-9xxx

Nothing known about 3w-9xxx.

Hardware using this driver:

aacraid

Adaptec provides RPMs with binaries for a command line tool afacli, capable of manipulating the raid sets, and with some effort extracting the current status of the raids. Dell also provides some admin tools in binary form. See [http://linux.dell.com/storage.shtml#aacraid], under the Management Utility heading.

Hardware using this driver: Dell ?PowerEdge 2650, Adaptec SCSI RAIDs 2200S, 2120S, SATA RAID 2810SA.

NB: I had some problems with Adaptec 2810SA. Debian kernel freezes (rejected IO to offline devices) in case array becomes downgraded (ie one disk failed). I've to patch kernel with adaptec driver, and kernel stops freezing with one drive fail -- AlexanderVlasov

cciss

The source for a daemon detecting status changes and reporting it to syslog and as SNMP traps [http://starbreeze.knoware.nl/~spark/compaq/ is available] and packaged for debian as cpqarrayd. Some information is available in /proc/driver/cciss/cciss0, but status on the raid is missing. The device names are not handled correctly by debian-installer. This is [http://bugs.skolelinux.no/show_bug.cgi?id=789 Skolelinux bug #789].

Hardware using this driver: Various servers from Compaq/HP, HP ?ProLiant DL380 G5

DAC960

Status info is available in /proc/rd/status. Dont use this with 2.4 kernels on machines with more than 1GB, as the driver has some problems accessing memory above 1GB

Hardware using this driver:

dpt_i2o

The source for some command line utils are available at [http://i2o.shadowconnect.com/download.php], and packaged for debian as raidutils.

Hardware using this driver: Adaptec SCSI RAIDs 2000S, 2100S, IDE RAID 2400A

gdth

Status info is available in /proc/scsi/gdth/0. Some tools and drivers are available [http://www.icp-vortex.com/english/support/faq/linux_e.htm from the vendor]. Some linux tools are available on a CD included with the controller. Debian packages storcon and srcd are hidden in ir1_linux_utils_2.12.zip downloadable from [http://downloadfinder.intel.com/scripts-df/Detail_Desc.asp?agr=N&ProductID=897&DwnldID=7497 Intel Download service].

Hardware using this driver: ICP Vortex GDT6118RD, Intel RAID Controller SRCZCR

ips

Info om BIOS-version and RAID configuration is available from /proc/scsi/ips/0. This file do not contain the RAID status. There is a precompiled command line tool ipssend available from the vendor CD. It can be used to get information on the RAID status, and also be used to configure and administrate the raid. There is also a graphical raid tool ?RaidMan available in RPM format from the vendor CD. The command line tool is also available from [http://linux-ha.org/download/ipssend.gz Linux-HA].

Hardware using this driver: IBM Netfinity 5500, IBM Netfinity 5600, IBM eserver xSeries 226, IBM eserver xSeries 345.

megaraid

Status info is supposed to be available in /proc/megaraid/*/raiddrives-*. This was not the case on at least one Dell ?PowerEdge 2550 machine. Some tools and drivers are available [http://linux.dell.com/files/megaraid/ from the vendor].

Hardware using this driver:

megaraid2

RAID-status is available from /proc/megaraid/*/raiddrives-* and disk-status from /proc/megaraid/*/diskdrives-ch*.

I had to rebuild initrd.img to get the megaraid2 driver on the ramdisk. The procedure I used was:

echo megaraid2>>/etc/mkinitrd/modules
mkinitrd -o /boot/initrd.img-megaraid2

Then I rebooted, and made sure that grub used the new initrd.img-megaraid2

Hardware using this driver: Dell PowerEdge 2850 megaraid_mbox [linux 2.6.9] Not aware of any method of detecting the RAID status for this RAID.

Hardware using this driver: Dell PowerEdge 2450, Dell PowerEdge 2850

mptscsih

RAID status is available using a the free [http://www.red-bean.com/~mab/mpt-status.html mpt-status tool].

Hardware using this driver: Sun v20Z, IBM eServer 325/326.