iii
Setting the spanning tree mode ···································································································································· 71
Configuring an MST region ·········································································································································· 71
Configuration restrictions and guidelines ··········································································································· 72
Configuration procedure ······································································································································ 72
Configuring the root bridge or a secondary root bridge ·························································································· 73
Configuring the current device as the root bridge of a specific spanning tree ·············································· 73
Configuring the current device as a secondary root bridge of a specific spanning tree ······························ 73
Configuring the device priority ····································································································································· 74
Configuring the maximum hops of an MST region ···································································································· 74
Configuring the network diameter of a switched network ························································································· 75
Configuring spanning tree timers ································································································································· 75
Configuring the timeout factor ······································································································································ 77
Configuring the maximum port rate ····························································································································· 77
Configuring edge ports ················································································································································· 78
Configuration restrictions and guidelines ··········································································································· 78
Configuration procedure ······································································································································ 78
Configuring path costs of ports ···································································································································· 78
Specifying a standard for the device to use when it calculates the default path cost ··································· 79
Configuring path costs of ports ···························································································································· 80
Path cost configuration example ·························································································································· 81
Configuring the port priority ········································································································································· 81
Configuring the port link type ······································································································································· 82
Configuration restrictions and guidelines ··········································································································· 82
Configuration procedure ······································································································································ 82
Configuring the mode a port uses to recognize and send MSTP packets ······························································· 83
Enabling outputting port state transition information ·································································································· 83
Enabling the spanning tree feature ······························································································································ 84
Enabling the spanning tree feature (in STP/RSTP/MSTP mode) ······································································ 84
Enabling the spanning tree feature (in PVST mode) ·························································································· 84
Performing mCheck ························································································································································ 85
Performing mCheck globally ································································································································ 85
Performing mCheck in interface view ················································································································· 85
Configuring digest snooping ········································································································································ 86
Configuration restrictions and guidelines ··········································································································· 86
Configuration procedure ······································································································································ 86
Configuration example ········································································································································· 87
Configuring no agreement check ································································································································· 88
Configuration prerequisites ·································································································································· 89
Configuration procedure ······································································································································ 89
Configuration example ········································································································································· 90
Configuring protection functions ·································································································································· 90
Enabling BPDU guard ··········································································································································· 90
Enabling root guard ·············································································································································· 91
Enabling loop guard ············································································································································· 91
Enabling TC-BPDU guard······································································································································ 92
Enabling BPDU drop ············································································································································· 93
Displaying and maintaining spanning tree protocols ································································································ 93
Spanning tree configuration examples ························································································································ 94
MSTP configuration example ······························································································································· 94
PVST configuration example ································································································································ 98
Configuring BPDU tunneling ··································································································································· 102
Overview ······································································································································································· 102
Background ·························································································································································· 102
BPDU tunneling implementation ························································································································· 103
