Hi All,
I am designing a VI3 environment for a client, however I am doubtful if HBAs will be a bottle neck for VM performance. I would like to know how many minimum I should recommend? Will two suffice one primary and another for failover? can we do load balancing for HBAs? I have read that we can have many number of VMs communicating through a single HBA however, will there be any performance issues? Can anybody share their experiences and recommendations?
Thanks
Rahul
I've not seen HBAs as a bottleneck, even more so with the 4GB HBAs now commonly available.
In our Blade Servers I have single dual port HBAs and in the 1 U Servers I have run 2 x single port HBAs.
The main SAN issues I've had have been a dodgy tranceiver and a fault motherboard on a Blade Server.
Otehrwise the HBAs themselves have been pretty sound which is why I'm not too concerned about going to single dual port HBAs on the Blade.
A lot of the design is about redundancy and how much risk / single points of failure you're prepared to tolerate.
Hi Rahul,
I think there should not be any problem to have multiple VMs over a single HBA.
I have 10 luns shared on to my machines with 8 to 10 VMs, and no issues on performance.
I'm not sure with the load balancing stuff over HBA, but make sure you have multi pathing enabled for the luns presented to that HBA.
-Karunakar
Hi
In general i don't see that you would have a bottle neck on your HBA. In most cases it's the CPU, Mem, Nic i/o.
But again it depends on the storage traffic.
So i would always go for 2 Hba per. host . This will give your redundancy and also, if your storage systems is active/active you will be able
to do loadbalancing.
My expirience is that we only utilize our HBA about 10-30 % in the most active esx host. That is hosting about 30 servers.
Best regards
Lars Liljeroth
-
If you found this information useful, please consider awarding points for "Correct" or "Helpful". Thanks!!!
Hi Lars / Karunakar,
Thanks for you comments and time you took for answering this. I think I understand what Karunakar is saying ...
However, lars are you saying that its ideal to have two HBA cards or 2 port * 2 HBA cards (total 4 ports) ? I also need to give RDMs to some of these VMs on that ESX with just 2 HBA ports will that affect anything?
Thanks and regards,
Rahul
I've not seen HBAs as a bottleneck, even more so with the 4GB HBAs now commonly available.
In our Blade Servers I have single dual port HBAs and in the 1 U Servers I have run 2 x single port HBAs.
The main SAN issues I've had have been a dodgy tranceiver and a fault motherboard on a Blade Server.
Otehrwise the HBAs themselves have been pretty sound which is why I'm not too concerned about going to single dual port HBAs on the Blade.
A lot of the design is about redundancy and how much risk / single points of failure you're prepared to tolerate.
I'd have to agree with the others. I've never seen HBA's being a bottleneck, even if all of the guests goes through a single one. And with nearly a hundred hosts, and thousands of guests, I'm sure I would have seen it if it were a likely issue.