Load Balancing SAN with Two Switches

I have Huawei Symantec OceanSpace S2600 ISCSI SAN with Dual Controller and each controller has upto 4x 1Gigabits connection.
My current layout is: I have two Vmware ESXI  Hosts and they connect to this shared SAN via iscsi interface, from each controller there are 2 x1 Gig output going to a Gigabit Switch and it’s been shared with ESXI Hosts.
I believe I have a bottleneck on bandwidth as my san is being heavily used for sql,exchange and  virtual servers running from it. Is it possible to introduce additional switch and load the balances between the two switches?
I want to bring the 2nd switch online and connect to the same controllers using the remaining output from each controllers.
I’m confused on how to bring the second Gigabit switch online and seen by 1st switch and both Esxi servers.

Please send me step by step instruction?
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

andyalderSaggar maker's framemakerCommented:
With 4 iSCSI ports per controller you don't really need switches at all. More info needed on your current topology - how many NICs do you have available in the ESXi hosts that you can dedicate to iSCSI?
PeterMatthewsAuthor Commented:
both ESXi servers have 2x 1Gigabit connection to the shared switch with iSCSI SAN.
I think it is a good idea a add a new switch to your configuration. I don't know if you could have better performance, but at least you will have high availability.

I understand that the performance bottleneck could be: 1) In the SAN network, or 2) In the SAN storage.

1) If you have a switch with more than 8 ports, maybe you can try to give those additional connections to the SAN controllers, just cabling and configuring. So it is cheap to try. But honestly, I think you will not get better performance. Neither if you add another switch and replicate everything.

If your servers have only 2 NICs, I think you need to add more. Purchase at least one 4x1Gb card for each one. Very important: configure different NICs for iSCSI, LAN and vMotion. In fact, it is a good practice to create 3 VLANs in the switches. There are lots of documentation about best practices regarding how to create the SAN network. Here you can see a very short and summarized one: http://www.littlerockcomputer.com/index.php?option=com_content&task=view&id=42&Itemid=1
But I recommend you to google about it.

2) Finally, maybe the bottleneck is not on your SAN network, but in the SAN storage. There are some tools that can help you identify IO performance in your storage environment. Please update the case with your disks (SATA or SAS?) and your RAID configuration. Snapshots?

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
A couple of links about it:

This last one is the "iSCSI SAN Configuration Guide" from vmware (v 4.x). 100 pages. Maybe it is the one you are looking for.
NIC teaming, VLANs, MTU size, aggregated links, jumbo frames... It is not easy to do, and not easy to explain here...

andyalderSaggar maker's framemakerCommented:
What a`waste of money since you don't need switches at all.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.