abaack
Contributor
Contributor

Optimal Setup for vSwitches?

Jump to solution

I used to have a setup with a bunch of different switches and each switch had it's own pnic, etc. Pretty much each assigned task (vmotion, iscsi, VM, SC) has their own assigned pnic.

After reading a Dell 'Best Practice' PDF file () I thought their way made a lot more sense than how I had mine setup. So here is how I'm thinking about doing it (following pretty close to their examples):

vSwitch0 (3 pnics connected to a Cisco 6509 in etherchannel):

-VM Traffic

-SC

-VMotion VMKernel (separate vlan)

vSwitch1 (2 pnics connected to a Cisco 6509 in etherchanel):

-iSCSI SC

-iSCSI VMKernel

Does this make sense? Also, how do I know which vSwitch is being used for iSCSI traffic since I don't see an option of turning on iSCSI like there is for turning on VMotion?

Thanks.

0 Kudos
1 Solution

Accepted Solutions
Chuck8773
Hot Shot
Hot Shot

Since the service console is only used for the discovery of the volume, not the connection traffic, it won't really matter. I am not sure which one it will use, and am a little surprised that you were able to create 2 service console ports in the same subnet. I recall running into an error when I tried that. Maybe I am recalling something similar though.

I don't know of a way to determine which service console port it will use. Perhaps from the SAN side? Maybe that can tell you which IP performed the discovery. It may use either one at different times though. You should see the IP of the VMKernel connected to the volume though. That will assure you that the actual iSCSI traffic is on the correct vSwitch.

Charles Killmer, VCP

If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".

Charles Killmer, VCP4 If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".

View solution in original post

0 Kudos
3 Replies
Chuck8773
Hot Shot
Hot Shot

This looks good. The only thing I would watch for is VM Traffic contending with VMotion and management traffic. That should be ok with three ports though.

As for iSCSI, in 3.5, it uses the service console to find the targets, and the VMKernel for the iSCSI connection and data. It selects the service console and vmkernel that are in the same subnet as the SAN.

In vSphere 4, the service console is no longer needed for iSCSI. Additionally, you can specify which VMKernel ports to use.

Charles Killmer, VCP

If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".

Charles Killmer, VCP4 If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".
abaack
Contributor
Contributor

Great thanks! Unfortunately, our SAN is in the same network as our Server network (bad planning on our part a while ago, but we haven't had a chance to fix it).

So it looks like this:

vSwitch0:

SC - VLAN 15

VMKernel - VLAN 17 with VMotion Checked On

vSwitch 1:

SC - VLAN 15

VMKernel - VLAN 15 with VMOtion not Checked On

Since both SC are in the same subnet as the SAN, which switch would it use? vSwitch1 (I hope) since the VMKernel in vSwitch0 is in a different subnet?

Thanks again.

0 Kudos
Chuck8773
Hot Shot
Hot Shot

Since the service console is only used for the discovery of the volume, not the connection traffic, it won't really matter. I am not sure which one it will use, and am a little surprised that you were able to create 2 service console ports in the same subnet. I recall running into an error when I tried that. Maybe I am recalling something similar though.

I don't know of a way to determine which service console port it will use. Perhaps from the SAN side? Maybe that can tell you which IP performed the discovery. It may use either one at different times though. You should see the IP of the VMKernel connected to the volume though. That will assure you that the actual iSCSI traffic is on the correct vSwitch.

Charles Killmer, VCP

If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".

Charles Killmer, VCP4 If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".
0 Kudos