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
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