Trunking iSCSI?

[EshuunDara]

I've got a few servers with 4 gigabit ethernet NICs that are to be used for vSphere.  I also have two gigabit switches and a Dell SAN for them.  I have VMs that will be running on this hardware using multiple vlans, and set aside a vlan for iSCSI traffic.  I'm currently struggling to understand what will yield the best performance -- setting all 4 ports as trunk and creating 4 iSCSI vmkernels with one NIC each to maximize multipath, or setting up two dedicated NICs for storage on the iSCSI vlan and two ports as trunk for "regular" traffic.

Can anyone offer any advice as to which will yield better performance?

[mittim12]

It's always been best practice to have your storage network dedicated so I would go with the two dedicated iSCSI NICS.

[msemon1]

Solution 2 appears to be a better option. With this solution you have redundancy and fault tolerance. Also you are separting your network traffic from your storage traffic which is good. I don't think the small difference in performance is worth the lack of redundancy and fault tolerance.

[EshuunDara]

I agree that a dedicated network for the storage would be best.  However since I only have two switches and will not be getting more, the best I can do is dedicate two NICs for it.  Since the iSCSI traffic will be going over the same set of switches as the other traffic, does it really improve IO?

[depping]

I would dedicate two NICs and seperate iSCSI from VM/Console/vMotion traffic to ensure one will not push out the other. Use a different VLAN for each type of traffic!

Duncan (VCDX)

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