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Cisco Content Services Switch Routing and Bridging Configuration Guide
OL-8241-02
Chapter2 Configuring Spanning-Tree Bridging for the CSS
Configuring Spanning-Tree Bridge Priority
To set the bridge maximum age to 21, enter:
(config)# bridge max-age 21
To restore the default maximum age of 6, enter:
(config)# no bridge max-age
Configuring Spanning-Tree Bridge Priority
In spanning tree, the 2-octet field is prepended to the 6-octet MAC address to form
an 8-octet bridge identifier. The device with the lowest bridge identifier is
considered the highest priority bridge and becomes the root bridge. By default, the
bridge priority is set to 32768. Use the bridge priority command to set the
priority that the bridge spanning tree uses to choose the root bridge in the network.
The range for bridge priority is 0 to 65535.
For example:
(config)# bridge priority 1700
To restore the bridge priority to the default of 32768, enter:
(config)# no bridge priority
Disabling Bridge Spanning-Tree
Spanning-tree bridging is enabled by default. When you disable spanning-tree
bridging, the CSS drops those bridge protocol data units (BPDUs) that it
recognizes as BPDUs, but forwards the Cisco Systems 802.1Q BPDUs (tagged
with the proprietary 01-00-0c-cc-cc-cc-cd destination MAC address) on an
802.1Q VLAN trunk. The CSS can still operate in an 802.1Q spanning-tree
environment as long as you do not require that the CSS put any of its ports into a
blocking state.
Caution Disabling spanning-tree bridging may make your network susceptible to packet
storms.