Dell PowerSwitch S4820T 9.50.1 Configuration Guide for the S4820T System - Page 790

NOTE: With large configurations (especially those configurations with more ports) Dell Networking recommends increasing the hello-time. The range is from 1 to 10. The default is 2 seconds. • Change the max-age parameter. PROTOCOL SPANNING TREE RSTP mode max-age seconds The range is from 6 to 40. The default is 20 seconds. To view the current values for global parameters, use the show spanning-tree rstp command from EXEC privilege mode. Enabling SNMP Traps for Root Elections and Topology Changes To enable SNMP traps, use the following command. • Enable SNMP traps for RSTP, MSTP, and PVST+ collectively. snmp-server enable traps xstp Modifying Interface Parameters On interfaces in Layer 2 mode, you can set the port cost and port priority values. • Port cost - a value that is based on the interface type. The previous table lists the default values. The greater the port cost, the less likely the port is selected to be a forwarding port. • Port priority - influences the likelihood that a port is selected to be a forwarding port in case that several ports have the same port cost. To change the port cost or priority of an interface, use the following commands. • Change the port cost of an interface. INTERFACE mode spanning-tree rstp cost cost The range is from 0 to 65535. The default is listed in the previous table. • Change the port priority of an interface. INTERFACE mode spanning-tree rstp priority priority-value The range is from 0 to 15. The default is 128. 790 Rapid Spanning Tree Protocol (RSTP)