2000-A2-GB20-10 - 123 - February 2004Enablingand Dis-abling STPHaving many bridges creates the potential for network loops. A looppresents conflicting information about the segment on which a specificaddress is located and forces the bridge to forward all data.When configuring the IAD as a router (Chapter 4, Router Configuration onpage 96), you must disable STP both globally and by port.Enabling or Disabling STP GloballyTo enable or disable STP globally:1. On the Bridge Configuration menu, type T to select Enable/DisableSpanning Tree Globally.The IAD displays the status of bridging, and a prompt:Spanning Tree is Globally DISABLEDEnter E to Enable, D to Disable:Type E to enable spanning tree globally, or D to disable it globally.2. The IAD saves, then displays the Bridge Configuration menu.3. Continue with other tasks, or press Escape to return to the Main menu.4. Reset the IAD (page 14) when you finish bridge configuration.Enabling or Disabling STP by PortTo enable or disable STP by port:1. On the Bridge Configuration menu, type O to select Enable/DisableSpanning Tree by Port.2. The IAD displays the interfaces available on this IAD, and a prompt:Available Interfaces:1. G2237 xDSL2. 10/100BaseT Ethernet0. (Abort)Type the number of the port for which you want to enable STP.3. If more than one interface is configured on the selected port, the IADdisplays a list of interfaces:Port DLCI Encapsulation1 18 Proprietary Voice DLCIType the number of the port.4. The IAD displays the status of this interface and port, and a prompt:Spanning tree over T1/E1 Port 1, is currentlyDISABLEDEnter E to Enable, D to Disable:Type E to enable STP on this port, or D to disable it.5. The IAD saves, then displays the Bridge Configuration menu.6. Repeat these steps for each port you want to enable or disable STP.7. Reset the IAD (page 14) when you finish bridge configuration.NOTE When you enable STP, the IAD reconfigures the bridgenetwork to transfer data along an optimum route to itsdestination.
