Order of priority for assigning VLANs

The assigned VLAN is determined, in order of priority, as follows:

  1. If there is a RADIUS-assigned VLAN, then, for the duration of the client session, the port belongs to this VLAN and temporarily drops all other VLAN memberships.
  2. If there is no RADIUS-assigned VLAN, then, for the duration of the client session, the port belongs to the authorized VLAN (auth-vid if configured) and temporarily drops all other VLAN memberships.
  3. If neither 1 or 2, above, apply, but the port is an untagged member of a statically configured, port-based VLAN, then the port remains in this VLAN.
  4. If neither 1, 2, or 3, above, apply, then the client session does not have access to any statically configured, untagged VLANs and client access is blocked.

The assigned port VLAN remains in place until the session ends. Clients can be forced to reauthenticate after a fixed period of time (reauth-period) or at any time during a session (reauthenticate). An implicit logoff period can be set if there is no activity from the client after a given amount of time (logoff-period). In addition, a session ends if the link on the port is lost, requiring reauthentication of all clients. Also, if a client moves from one port to another and client moves have not been enabled (client-moves) on the ports, the session ends and the client must reauthenticate for network access. At the end of the session the port returns to its pre-authentication state. Any changes to the port's VLAN memberships made while it is an authorized port take affect at the end of the session.

A client can not be authenticated due to invalid credentials or a RADIUS server timeout. The max-retries parameter specifies how many times a client can enter their credentials before authentication fails. The server-timeout parameter sets how long the switch waits to receive a response from the RADIUS server before timing out. The max-requests parameter specifies how many authentication attempts can result in a RADIUS server timeout before authentication fails. The switch waits a specified amount of time (quiet-period) before processing any new authentication requests from the client.

Network administrators can assign unauthenticated clients to a specific static, untagged VLAN (unauth-vid), to provide access to specific (guest) network resources. If no VLAN is assigned to unauthenticated clients the port is blocked and no network access is available. Should another client successfully authenticate through that port any unauthenticated clients on the unauth-vid are dropped from the port.