To support VLANs for VMware Infrastructure users, the virtual or physical network must tag the Ethernet frames with 802.1Q tags using virtual switch tagging (VST), virtual machine guest tagging (VGT), or external switch tagging (EST). If you’re looking for how to configure VLAN tagging in VMware vSphere, you may refer to VMware KB 1004074 & KB 1004252.

Last week I have configured a VLAN tagging on one of my vSphere 4 Update 2 cluster and due to some reason, I have remove the VLAN ID manually.

VLAN ID not remove

After hard reboot, the VLAN ID remains and it’s not removing from Port Group. I was surprised and I guess probably this is a bug for vSphere Update 2? Again, I tried with manual reboot and it’s worked. All the VLAN ID has been removed.

Anyway, I do not make VMware support report and if you have similar case, please feel free to share with me.