By default, a virtual NIC (VM NIC) on a guest VM operates in access mode. In this mode, the VM NIC can send and receive traffic only over its own specified VLAN. If restricted to using access mode interfaces, a VM running an application on multiple VLANs (such as a firewall application) must use multiple VM NICs—one for each VLAN. Instead of configuring multiple VM NICs in access mode, you can configure a single VM NIC to operate in trunked mode. A VM NIC in trunked mode can send and receive traffic over any number of VLANs in addition to its own VLAN. You can trunk specific VLANs or all VLANs. A VM NIC in trunk mode can convert back to access mode, meaning the VM NIC reverts to sending and receiving traffic only over its own VLAN.

Steps :-

acli vm.nic get <vm_name>

acli vm.nic_create  <VM_name> network=<net_name> vlan_mode=kTrunked  trunked_networks=<comma separated VLAN ID list>

To update an existing virtual NIC from access mode to trunked mode.

acli vm.nic_update  <VM_name>  <vm_mac_addr>  update_vlan_trunk_info=true  vlan_mode=kTrunked  trunked_networks=100,200,300

acli vm.get  <vm_name>