VMPS Configuration

With the VLAN Membership Policy Server (VMPS) Configuration window, you can:

Dynamic VLAN membership assigns end stations to VLANs when needed. The switch functions as the VLAN Query Protocol (VQP) client that queries the VMPS, such as a Catalyst 5000 switch. The server must be configured before you configure a dynamic-access port for the connection to the end-station. (For more information about configuring and troubleshooting the Catalyst 5000 switch as the VMPS, see the Catalyst 5000 Series Software Configuration Guide; for information on configuring dynamic-access ports, see the VLAN Membership help file.)

Initially, the dynamic-access port does not belong to a VLAN. No traffic is forwarded to or from this port. When the client receives the first packet from a new host on its dynamic-access port, it uses VQP to send the source MAC address to the VMPS. The VMPS provides the VLAN name to which this port must be assigned. The VMPS can also send an access denied or a port shutdown response if the VLAN is illegal on the port.

Caution: Dynamic-access ports are designed to work with end stations. Loss of connectivity can occur if you connect dynamic-access ports to switches or routers.

Viewing VMPS Information

Fields in the VMPS Info tab have the following meaning:

Field Description
VLAN Query Protocol Version The VQP client sends only VQP version 1 requests to the VMPS for VLAN assignment. This field is read-only.
Current VMPS The address of the VMPS server currently responding to VQP client requests. If no secondary servers are configured, the current VMPS server address and the primary VMPS server address are the same. By default, no primary or secondary servers are configured. If the current server is not the primary server, the switch tries to contact the primary server every 5 minutes. If contact is reestablished, the primary server becomes the current server again. This field is read-only.
Primary VMPS The address of the primary VMPS server that responds to VQP client requests. By default, no primary servers are configured. This field is read-only.
Number of Retries Number of times a client repeats requests if the VMPS does not respond. The default number of retries is 3, but you can change it (see Setting VMPS Client Parameter).
Reconfirmation Interval Queries are periodically sent to reconfirm VLAN membership of addresses already learned on the port. By default, these messages are sent every 60 minutes, but you can change the interval (see Setting VMPS Client Parameters). The following status messages are valid:
- reconfirm in progress
- reconfirm completed successfully
- reconfirm failed because no VMPS responded
- no VMPS configured
- no dynamic port configured
- no hosts on dynamic port
- no reconfirmation has been done

Setting VMPS Client Parameters

By default, the client queries the VMPS every 60 minutes to reconfirm all VLAN assignments. You can change the reconfirmation interval or reconfirm the assignments on demand.

  1. Select the VMPS Info tab on the VMPS Configuration window.
  2. In the Number of Retries field, enter a number from 1 to 10 (the default is 3) to adjust the number of times the client tries to reach the current server before switching to an alternate.
  3. In the Reconfirmation Interval field, enter a number from 1 to 120 to adjust the reconfirmation interval, if necessary.
    The default is 60 minutes.
  4. Click Apply to put your changes on this tab in effect.
  5. Click OK to close the VMPS Configuration window.

To reconfirm dynamic VLAN membership, click Refresh in the Reconfirmation Membership section.

Configuring a Switch for Dynamic VLAN Membership

Before configuring the switch (VMPS client) for dynamic VLAN membership, you must first set up the VMPS server. For information on setting up and troubleshooting the server, see the Catalyst 5000 Series Software Configuration Guide or the appropriate documentation.

To configure the client for dynamic VLAN membership:

  1. Select the VMPS Server tab on the VMPS Configuration window.
  2. In the New Server IP field, enter the IP address of the VMPS server to be queried by the client.
  3. Click Add to add the server IP to the VMPS Servers list.
  4. To designate the primary server, highlight the IP address of the server in the list box, and click Make Primary.
    Note: Only one address can be primary.
  5. Repeat steps 2 and 3 to designate secondary VMPS servers.
    The client queries secondary servers if no response is received from the primary VMPS. You can enter up to three secondary server addresses.
    Note: To override the primary server, highlight a secondary address in the VMPS Servers list and click Make Primary.
  6. Verify that VTP domain name is correctly configured:
    From the menu bar, select VLAN > VTP Management.
  7. Select the VTP Configuration tab and verify that the domain name is the same as in the VMPS configuration file.
  8. Assign a port as dynamic.
    From the menu bar, select VLAN > VLAN Membership.
  9. On the Assign VLANs tab, select the port and set it to Dynamic Access.
    See VLAN Membership help topics for details.
  10. Click Apply to put your changes on this tab in effect.
  11. Click OK to close the VMPS Configuration window.

Removing a VMPS Address

To remove a server from the list of designated VMPS servers:

  1. Select the VMPS Server tab on the VMPS Configuration window.
  2. In the list box, select an address to highlight it.
  3. Click Remove.
  4. Click Apply to put your changes on this tab in effect.
  5. Click OK close the VMPS Configuration window.

Note: If you delete all servers when dynamic-access ports are present, the switch cannot forward packets from new sources on these ports because it cannot query the VMPS.