RAID

From Nuclear Physics Group Documentation Pages
Jump to navigationJump to search

RAID Controllers

Hostname RAID Controller OS User Manual Web Interface Address
Taro.unh.edu Areca Technology Corp. ARC-1231 12-Port PCI-Express RHEL 5 Areca ARC-1xxx http://10.0.0.97/
Pumpkin.unh.edu Areca Technology Corp. ARC-1231 12-Port PCI-Express RHEL 5 Areca ARC-1xxx http://10.0.0.99/
Gourd.unh.edu Areca Technology Corp. ARC-1680 8-port PCIe SAS RAID Adpater RHEL 5 Areca ARC-168x http://10.0.0.152
Tomato.unh.edu 3ware Inc 9000-series RHEL 3.4 - -
Old Gourd Promise Technology, Inc. PDC20378 (FastTrak 378/SATA 378) RHEL 3.4 - -
? 3ware Inc 7xxx/8xxx-series PATA/SATA-RAID - - -
Pepper.unh.edu Silicon Image, Inc. SiI 3114 RHEL 3.4 - -
Old Einstein Marvell Technology Group Ltd. MV88SX6081 8-port SATA II PCI-X RHEL 5.3 - -

New RAID cards: ARECA

The Areca cards in Pumpkin, Taro and Gourd (the new Einstein hardware) can all be accessed with a web browser. The interfaces are all on the backend network:

You log in as "admin" with the standard root password missing the prefix part.

Working with Areca RAID devices

These are my notes from testing out the Areca card in Gourd, and should serve as brief howtos for various features of the RAID cards.

Pass-through drives

Pass-through drives are not controlled by the RAID card. They function as an independent scsi device plugged directly into the system, and are not part of a RAID set. These are the steps I took to add a new pass-through device on [Gourd]:

1. Insert the drive into the drive bay
2. The drive should now be visible in the Areca web interface. Expand the "Physical Drives" folder in the left column and then select "Create a Pass-Through disk".
3. Select the disk you want to create as a pass-through disk and then check the confirmation box before clicking the Submit button.
4. The disk is now configured as a pass-through disk, but it won't be visible to the system. You need to add it to the scsi subsystem. This can be accomplished using the proc interface scsi commands. This is a decent guide to understanding how to use these commands. The values for Channel, SCSI ID and Lun can be obtained from the Areca card's web interface under Information/RAID Set Hierarchy.
This is the command I used to add the first pass-through drive I created. Note that for this to work you have to be logged in as root (sudo won't work):

root@gourd# echo "scsi add-single-device 0 0 0 1" > /proc/scsi/scsi

Once you've run this command your drive should now appear in /dev/sd* with the other scsi devices. To remove this device you would use a similar command:

root@gourd# echo "scsi remove-single-device 0 0 0 1" > /proc/scsi/scsi

Possible rescue techniques

DO NOT ATTEMPT THIS WITHOUT TOP SUPERVISOR PRESENT

some unchecked advice in a forum

Old RAID cards

The documentation for the controller should be available in /usr/local/doc/3dm2. There should be a deamon running, start it with "/etc/init.d/3dm2 start" With the deamon running, the device can be checked and manipulated using a web browser on the local machine pointing to http://localhost:888/. Log in as administrator with the root password.

More recently (2006) we no longer run this deamon, instead the RAIDS can be querried and controlled with tw_cli, in /usr/local/bin. Type tw_cli help for help. You must be root to run this program.

Examples (must be root):

tw_cli help info
tw_cli info c0     # info for card 0
tw_cli info c0 u0    # info for unit 0, Tells you it is RAID-5, Status OK, size, Stripe size
tw_cli info c0 p0  # info on disk0 on card0, size, serial number.
tw_cli info c0 p0 model # model number of disk (Maxtor 6B200S0)

Be totally wicked careful with any of the other commands PLEASE

TOMATO:

Contains a RAID with 12 Maxtor Diamond Max 10 drives (300GB, model number: 6B300S0). Data Sheet

Size: 300 GB
Spin: 7200 RPM
Buffer:  16 MB
Seek: <9 ms
Latency: 4.17 ms]
Current/Power - not specified. 1.2 Amp/ 15 Watt is a good guess

OLD GOURD:

Contains a RAID with 8 Maxtor drives (251GB, Model number 7Y250M0)