Bridge Priority

By configuring the STPD bridge priority, you make the bridge more or less likely to become the root bridge.

Unlike the 802.1D-1998 standard, the 802.1D-2004 standard restricts the bridge priority to a 16-bit number that must be a multiple of 4,096. The new priority range is 0 to 61,440 and is subject to the multiple of 4,096 restriction. The old priority range was 0 to 65,535 and was not subject to the multiple of 4,096 restriction (except for MSTP configurations). The default bridge priority remains the same at 32,768.

If you have an ExtremeXOS 11.5 or earlier configuration that contains an STP or RSTP bridge priority that is not a multiple of 4,096, the switch rejects the entry and the bridge priority returns to the default value while loading the structure. The MSTP implementation in ExtremeXOS already uses multiples of 4,096 to determine the bridge priority.

To configure the bridge priority, use the following command:

configure stpd stpd_name priority priority

For example, to lower the numerical value of the priority (which gives the priority a higher precedence), you subtract 4,096 from the default priority: 32,768 - 4,096 = 28,672. If you modify the priority by a value other than 4,096, the switch automatically changes the priority to the lower priority value. For example, if you configure a priority of 31,000, the switch automatically changes the priority to 28,672.