vswitch with NIC teaming

No...it means you have 2 1-Gig NICs for use. Traffic can pass thru either 1. Make sense?

~coolsport00

It will not utilize 2GB unless a few things happen and depending on what you want to use the vswitch for.  

If a virtual machine network port group then vmware will dividing the VMs across the nics.  If you're using it for iSCSI (vmkernel port) a few things would need to occur for you to get both nics to work simultenousely

if they are trunked, etherchannelled, port grouped, channel grouped at the physical switch. they could use 2Gb of throughput, but only if you change the networking in the Virtual Machine to VMXNET3 adaptors. (E1000 are limited to 1GBps)

To add to what @hanccocka stated, this depends..If you're doing vmkernel to NFS you'll not be able to get 2GB because the session can't go over a physical nic.  For iSCSI you can only do this if you setup multipathing and multiple vmkernel ports, otherwise same issue, you can't go over a single session on a single physical nic no matter hot many nics are in a LAG or etherchannel.

I don't know currently how many physical NICs you have connected from the virtual switch to the physical switch. But lets say you have two for the sake of agrument, if these are channel grouped, etherchannel or bonded/teamed, what ever technology you are using, Cisco/HP etc all use different terminology.

With a 1Gb NIC, (E1000), your VM has access to 1Gb of throughput.

If you feel you don't have enough bandwidth/throughput (based on checking network statistics and metrics), what you could do is:-

1. Use the VMXNET3 NIC in the Virtual Machine, this will connect the VM to the switch.

So you should be able to get some throughout near to 2Gb.

If you add more physical NICs, add another two, you may get near to 4Gb of throughput.

So in Summary.

1. Ensure VMware Tools is installed.
2. Change to VMXNET3 NIC
 
but to see ther benefit, you'll need more physical network cards in the ESX server, and bonded, channel grouped, etherchannel etc

Only way you can get more than 1GB is if you're doing multiple sessions, this is the piece most people miss.  If your server is connecting to a single PC or server (one to one IP) the max you can have is one session which can't leave a physical nic port.  If you're running 10GB nic than it's a moot point, otherwise it's 1GB max.

thanks guys for your input on this.

Here is what my understanding of the issue.

say I have 2 1GB NICs assigned to a vswitch for vmworkstation portgroup. There is no NIC teaming/binding at the physical switch side, can I say that VMs network traffic on the vswitch will be evenly distributed over the 2 1 GB NICs, therefore, the max throughput is 1 GB.

If there is NIC teaming/channel created on the physical switch side, then the max throughtput  will be 2 GB? assuming all VMs are using VMXNET3 adapter? i thought VMXNET3 is only 1 GBPs adapter also.


I thought adding multiple NICs to the vswitch can provide load balancing and failover, so what confuse me right now is i am not sure how vswitch load balance the network from VMs. if i have 4  VMs on the same switch all using full 1 GB at the same time, how vswitch deal with that?

Thanks guys for your help in advance!

and for this comment:

If a virtual machine network port group then vmware will dividing the VMs across the nics.  If you're using it for iSCSI (vmkernel port) a few things would need to occur for you to get both nics to work simultenousely


sounds like if for vm network port group, no matter what, only 1 NIC will be used at a given time.

and if for vmkernal port, what must be done so both NICs can be used at the same time? will there still be load balancing and fault tolerant if both NICs are used to increase throughput?

Thanks

1 nic for each session.  If you have multiple workstations connecting to a single server and you have etherchannel configured then you will have multiple sesssions thus using multiple nics

for vmkernel you can setup multipath for iscsi (2 vmkernel ports and round robin on the datastore) unless you have iSCSI HBAs which will take care of most of this for you

Hi Paul,

I am not sure i underrstand your comment: could you explain what you mean by 1 nic for each session> and what do you mean by having multiple workstations connecting to a single server? I am lost.

Thanks