You can delete VLANs that are configured on network ports by using System Manager. You might have to delete a VLAN before removing a NIC from its slot. When you delete a VLAN, the VLAN is automatically removed from all of the failover rules and groups that use the VLAN.
No LIFs must be associated with the VLAN.
Click Network > Ethernet Ports.
Select the VLAN that you want to delete, and then click Delete.
Select the confirmation check box, and then click Delete.