Has anyone changed the MTU on a vDS with VMs running ?

[pmichelli]

I found this KB : https://kb.vmware.com/s/article/1038827

It says if you change the MTU to 9000 on a vDS , that it will briefly bring all the uplinks down and back up again.

Has anyone done this ? I am a bit concerned because everything but the iSCSI is on this vDS. I worry something will happen to the management interfaces on the connected ESXi hosts.  I can't really do a full shutdown on all the machines to make this change.

[aakalan]

I did million times, never affected production.

We are not using iSCSi. all the VMs are using 1500 MTU. only vMotion and vSAN traffic is using 9000.

[bryanoconnor21]

Because of network rollback set on the management network you should find that no changes will be made to the management networks https://docs.vmware.com/en/VMware-vSphere/7.0/com.vmware.vsphere.networking.doc/GUID-88B9F893-9739-4...

[lukaszzasko]

II do this all the time during implementation of NSX - it shouldn't impact on running services. If you decided to enable jumbo frames on VDS level you must do it same in vmkernel adapter also.