Number of NICS?

[hurdle]

As servers become more and more robust I have noticed consolidation ratios have the potentional to increase as well.

There are many doc's out there on sizing from a memory/processor perspective but I have not seen much on the number of NICS per host dedicted for the VM Network. Now I know this number can vary in terms of type of traffic ect... But is there a base number out there that anyone is aware of? At what point does the standard two ports not sufficient? What effect does vlan tagging have on a virtual switch ect....

There is always the wait to see what it looks like but in enviroment such as a blade where you are limited to how many nics you need a reactive aproach is not always exceptable.

[amvmware]

That is one of the limitations of a blade infrastructure - although you can get upto 8 nic ports in a lot of the blades these days.

I generally assign 2 nics for VM traffic and never had an issue - but these are your general Infrastructure servers - file, print, email, web...etc.

If you have an application that you believe is network intensive then it would make sense to understand the bandwidth requirements before virtualising it.

With blades these days you also have the ability to flex the bandwidth.

[krismcewan]

A general rule about Nics is get as many as you can.

I have seen some users with 12 nics for a dozen or so VM's using Iscsi. 4 for Iscsi, 2 for Vmotion, 2 for DMZ and 4 for production.

Beware with some Blades. trade off on extra nics can come at the cost of HBA's so if you have Fibre cards you may only get a max of 4 Nics.

A VMware Consultant in Scotland for Taupo Consulting

If you think I'm right or helpful award me some points please

[vmroyale]

Hello.

Now I know this number can vary in terms of type of traffic ect... But is there a base number out there that anyone is aware of?

Obviously, one is required and two would be better for redundancy. But like you said, it is going to be different for each environment. In a very small shop with a single flat network, 2 nics might be sufficient for both the management and virtual machine traffic. If the size of the shop increases, then that number may need to go up to accommodate shared IP storage, vMotion, etc. This variety of requirements in the setup is why there isn't really a published base number to work with.

At what point does the standard two ports not sufficient?

When you need separation of management from virtual machine networks with redundancy.

When you add IP-based storage.

When you need to use other advanced features like vMotion or FT.

The requirements of the setup will ultimately dictate the number of nics required.

Good Luck!