topic Re: RAID level in Disk Enclosures

RAID level

Nguyen Anh Tien — Thu, 29 Jul 2004 01:34:02 GMT

I read this message "the same disk within a redundancy group can have one portion of its data capacity stored in RAID 1+0, while the other portion is stored in RAID 5DP" in HP surestore Virtual Array VA7100 and VA7400 but I do not understand How AutoRaid works? How does AutoRaid store data and recover?

Re: RAID level

Uwe Zessin — Thu, 29 Jul 2004 03:06:42 GMT

AutoRAID does not store and recover data - it is not a RAID-level like 0/1, 5DP. It means that some portions of a single virtual disk can be stored in RAID 1+0 and other portions of that same virtual disk in RAID5DP. The VA decides which portion is stored in which level depending on the free space of the array (if I recall correctly, it starts with RAID5DP, when the free space has dropped to 50%) and the I/Os - portions that are accessed often will be stored in RAID 1+0.

Re: RAID level

Nguyen Anh Tien — Thu, 29 Jul 2004 03:57:53 GMT

How can I check what Raid level my VA are using?

Re: RAID level

Rithu Kumble — Mon, 02 Aug 2004 04:50:31 GMT

Hi Nguyen Anh Tien

You can verify the RAID level for VA using the Command View SDM software that is installed on your host machine. These are the steps you need to follow:

1) Start the GUI using the /commandview/client/sbin/cmdviewva :

2) Go to Configurations, and then General Settings. The subsequent screen displays the current RAID level. The field name is ' Subsystem Level RAID Control: '

The current RAID level can be HP AutoRAID or RAID 0+1.

I hope this helps. Have a great day.

Regards
Rithu Kumble

Re: RAID level

Nguyen Anh Tien — Mon, 02 Aug 2004 20:28:33 GMT

how can i caculate space for my VA.
For example. I want to add 120GB to my VA (running in AutoRAID mode), which formula can I use? I want to caculate how many disks I should buy more.
Thank.