Creating VLANs on RAMix Ethernet Switches

VLAN - Virtual LAN.  A logically-independent network.  Usually several VLANs will coexist on a single network switch.

VLAN Tag - Defined in IEEE 802.1Q .  Four bytes are added to the Ethernet header for identification.  The EtherType field is changed to 0x8100, indicating that a VLAN tag is present in the frame.  This is then followed by a header that defines user_priority (3-bits), the Canonical Format Indicator (CFI, 1-bit), and the VLAN ID (VID, 12-bits).  The 12-bits for VID will allow a theoretical maximum of 4096 VLANs.

Egress Port List - These are the ports that belong to the VLAN.  A broadcast packet sent on this VLAN will be sent to every port in this list.

Forbidden Egress Port - This is a list of ports that are forbidden to send out packets belonging to this VLAN.

Untagged Port List - Untagged packets arriving on these ports on these ports will be assigned to this VLAN.

Creating a VLAN

  • Login to switch as 'admin'
  • Switch> vlan
  • Switch vlan> create

Notes on creating VLANs

  1. Operator input is shown in bold text.
  2. For null fields, such as when no forbidden ports are desired, enter a dash {-} in that fields position.

Examples of Creating VLANs

  • To create VLAN # 4, consisting of ports 20, 21, 22, with port # 23 forbidden, and port # 20 as untagged.
  • Switch vlan> create  4  20,21,22  23  20

To create VLAN #5, consisting of ports 10, 11, and 12, with no forbidden or untagged ports.

  • Switch vlan> create  5  10,11,12  -  -


  • CP/RM920, CP/RM921, RM922 Gigabit Switches - Operators Reference Manual
  • GE Fanuc Document Number: Rx-URMO Rev A  (DRAFT - currently undergoing revision)
  • 93x Ethernet Switch Family - Operators Reference Manual
  • GE Fanuc Document Number: Rx-URMO 070 Rev J
  • Managed Layer 2 Ethernet Switch Family
  • GE Fanuc Document Number: Rx-URMO 146 Rev 4, "The Switch Book"  Seifert, Rich ©2000 Wiley Computer Publishing, ISBN:  0-471-34586-5