topic Re: about redundancy group in va7410 in Disk Enclosures

about redundancy group in va7410

vofsky — Wed, 08 Oct 2003 21:08:44 GMT

Who could tell me what function of the redundancy group is?Can I put the lun in redundancy group 1 or redundancy group 2 when I create a lun?Pls give me a hand.

Re: about redundancy group in va7410

Eugeny Brychkov — Thu, 09 Oct 2003 01:45:42 GMT

Under normal conditions RG1 is managed by C1 and RG2 is managed by C2. If controller fails that one survived controller manages both RGs.
So you may consider VA as a set of 2 redundant arrays - RG1 (odd disks) and RG2 (even disks).
Each RG has its own active hotspare space, its own total, allocated and unallocated space.
Check manuals at http://h20000.www2.hp.com/bizsupport/TechSupport/DocumentIndex.jsp?contentType=SupportManual&locale=en_US&docIndexId=179111&taskId=115&prodTypeId=12169&prodSeriesId=89018
Eugeny

Re: about redundancy group in va7410

vofsky — Thu, 09 Oct 2003 17:33:53 GMT

Hi Eugeny ,
Can I ask some carified question to you?The failed controller includes the problem caused by fibre channel cable and adapter,is it correct?If there is just one controller available(for example A is available),can I create the lun in the rg2 since there is not enough space left in the rg1?Thank you for your help.

Re: about redundancy group in va7410

Eugeny Brychkov — Fri, 10 Oct 2003 01:05:20 GMT

Both controllers are synchronized. When both are good then when accessing LUN through its non-owning controller then this controller forwards I/Os to/from owning controller - that's why it's recommended to have primary path through owning controller (important for VA7x00, not so important for new VA7x10).
When one of controllers fails then another controller takes ownership of all LUNs of all RGs.
Thus if you have FC cable failure then you can access only one VA controller and as soon as another owning controller is still alive I/Os will be forwarded to LUNs within owned RG
Eugeny