Showing results for 
Search instead for 
Did you mean: 

steps to enable jumbo frame , 1000v , vmware?

Cisco Employee
Cisco Employee

hi friends..

can someone give me all the steps to enable jumbo frame on a 1000v environment... i already set all my vnics on ucs to mtu 9000 , so do i need to set anything on the port profiles?

i was thinking

1) set mtu 9000 on ucs vnics

2) set system jumboframe mtu on 1000v

3) set mtu 9000 in all port channels

4) set mtu 9000 on vmkernel interfaces (in esxi comand line)

am i missing something??

3 Replies 3


Hi Marcos,

The steps / sequence mentioned by you are correct.



Hi Marcos, I don't think the E1000 adapter which is the Nexus 1000v's default adapter from the install is supported for Jumbo Frames, I thought only vmxnet3 is ?

You're correct - the e1000 doesn't support jumbo frames.  You'll need to use VMXNET2 or VMXNET3 for VMs requiring jumbo frame transmission.  The question above references VMKernel ports, not VM ports, so we assume he's referencing jumbo frames support for the host - either iSCSI or NFS access.

In regards to the Nexus 1000v's VSM interfaces using e1000 - this isn't an issue.  Keep in mind the VSM's interfaces are for control & management traffic only - NOT data plane traffic (such as IP storage).

Jumbo frames have to be configured end-to-end to provide any value.  The only networks/VLANs people normally enable them are for IP storage access.  It's critical to test jumbo frames access with vmkpings of larger packet size to ensure you have no bottlenecks.  If you can't hit end to end with at least a 8960 packet then create an SVI on each upstream device in the corresponding VLAN and test each hop until you find out where MTU gap is.



Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Recognize Your Peers