topic Re: Balancing ESX LUNs across controllers on EVA8000 in Operating System - VMware

Balancing ESX LUNs across controllers on EVA8000

Mel Nugent — Tue, 02 Nov 2010 16:25:23 GMT

I want to balance the Vdisks on the EVA across the controllers as some were set to no preference and some to failover/failback etc.

I have 2 EVA 8000 with CA replication. Each one has a c7000 blade enclosure with 4xBL680c blades running ESX3.5
So far I have listed all the presented VMware Vdisks on one EVA and then grouped all the Vdisks by DR group (as I think all Vdisks in a DR group have the same owning controller). I have then set all DR group1 to controller A failover/failback then DR group2 to controller B Failover/Failback and so on. Any Vdisks not replicated I have mixed between A and B.
On the ESX side I have set all Vdisks to fixed and set the preferred path to either WWWN ending in 8,9,A,B, for controller A and ending in C,D,E,F for controller B.

I think this should leave me with Vdisks balanced across controller and also across port on each controller. Can anyone confirm this is OK?
Should I also set the destination replicated Vdisks to failover/failback also and balance across controllers even though they are not presented?
Thanks

Re: Balancing ESX LUNs across controllers on EVA8000

Oscar_Maimó — Wed, 03 Nov 2010 13:46:14 GMT

First of all:
What version of ESX do you have?
ESX 3.5.x or ESX 4.x
This detail is very important because storage architecture changes a lot between versions.
Greetings
Oscar

Re: Balancing ESX LUNs across controllers on EVA8000

Mel Nugent — Wed, 03 Nov 2010 13:50:55 GMT

Thanks Oscar.

I have 2 EVA 8000 with CA replication. Each one has a c7000 blade enclosure with 4xBL680c blades running ESX3.5
3.5.0, 207095 being full version details.

Re: Balancing ESX LUNs across controllers on EVA8000

Oscar_Maimó — Wed, 03 Nov 2010 14:16:40 GMT

Be carefully with multipath options in ESX 3.5. This version is not ALUA compliant, it means it is possible that a host may access a LUN from a proxy controller resulting in a performance degradation because the read request must go across mirror port to the owner controller. Also if a LUN is acceded from two different hosts, across different controllers path trashing may ocurr, resulting in performance degradation too.
Greetings
Oscar

Re: Balancing ESX LUNs across controllers on EVA8000

Mel Nugent — Tue, 16 Nov 2010 16:23:48 GMT

I have balanced the LUNS as described and will run EVA perf on them to see if any other amendments need to be made.