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tech:network:cisco:stp:loopguard:loopguard

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tech:network:cisco:stp:loopguard:loopguard [2019/06/08 07:09] (current)
wnoguchi created
Line 1: Line 1:
 +====== STP: Loop Guard ======
 +
 +{{tag>​Loop-Guard STP Catalyst Cisco Networking}}
 +
 +===== Topology =====
 +
 +{{:​tech:​network:​cisco:​stp:​bpduguard:​pasted:​20190607-233341.png}}
 +
 +==== Log ====
 +
 +  - loopguard verification is difficult...
 +  - loopguard, rootguard can configure exclusively. when loopguard enabled default, roop guard configuration works in Catalyst 2960 15.x.
 +
 +<​code>​
 +SW1#conf t
 +Enter configuration commands, one per line.  End with CNTL/Z.
 +SW1(config)#​spa
 +SW1(config)#​spann ​        
 +SW1(config)#​spanning-tree loopgu
 +SW1(config)#​spanning-tree loopguard defa
 +SW1(config)#​spanning-tree loopguard default ​
 +SW1(config)#​^Z
 +SW1#
 +*Mar  1 09:​01:​55.258:​ %SYS-5-CONFIG_I:​ Configured from console by console
 +SW1#
 +*Mar  1 09:​03:​51.868:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/1
 +*Mar  1 09:​03:​51.885:​ STP: VLAN0001 we are the spanning tree root
 +*Mar  1 09:​03:​51.885:​ STP[1]: Generating TC trap for port FastEthernet1/​0/​2
 +SW1#
 +*Mar  1 09:​03:​52.892:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface FastEthernet1/​0/​2,​ changed state to down
 +*Mar  1 09:​03:​53.898:​ %LINK-3-UPDOWN:​ Interface FastEthernet1/​0/​2,​ changed state to down
 +SW1#
 +*Mar  1 09:​05:​43.772:​ set portid: VLAN0001 Fa1/0/2: new port id 8004
 +*Mar  1 09:​05:​43.772:​ STP: VLAN0001 Fa1/0/2 -> listening
 +SW1#
 +*Mar  1 09:​05:​45.769:​ %LINK-3-UPDOWN:​ Interface FastEthernet1/​0/​2,​ changed state to up
 +*Mar  1 09:​05:​46.775:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface FastEthernet1/​0/​2,​ changed state to up
 +SW1#
 +*Mar  1 09:​05:​58.779:​ STP: VLAN0001 Fa1/0/2 -> learning
 +SW1#
 +*Mar  1 09:​06:​13.745:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/2
 +*Mar  1 09:​06:​13.770:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/1
 +*Mar  1 09:​06:​13.787:​ STP[1]: Generating TC trap for port FastEthernet1/​0/​2
 +*Mar  1 09:​06:​13.787:​ STP: VLAN0001 Fa1/0/2 -> forwarding
 +*Mar  1 09:​06:​13.812:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/2
 +SW1#
 +*Mar  1 09:​06:​37.770:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/2
 +SW1#
 +*Mar  1 09:​07:​28.655:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/2
 +SW1#
 +*Mar  1 09:​08:​47.810:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/2
 +SW1#sh spa
 +SW1#sh spanning-tree ​
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   8193
 +             ​Address ​    ​e8ed.f315.9380
 +             This bridge is the root
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   8193   ​(priority 8192 sys-id-ext 1)
 +             ​Address ​    ​e8ed.f315.9380
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  15  sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa1/​0/​1 ​            Desg FWD 19        128.3    P2p 
 +Fa1/​0/​2 ​            Desg FWD 19        128.4    P2p 
 +
 +
 +SW1#
 +*Mar  1 09:​09:​16.826:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/2
 +SW1#conf t
 +Enter configuration commands, one per line.  End with CNTL/Z.
 +SW1(config)#​do sh ip int vlan 1
 +Vlan1 is up, line protocol is up
 +  Internet address is 172.16.0.11/​24
 +  Broadcast address is 255.255.255.255
 +  Address determined by setup command
 +  MTU is 1500 bytes
 +  Helper address is not set
 +  Directed broadcast forwarding is disabled
 +  Outgoing access list is not set
 +  Inbound ​ access list is not set
 +  Proxy ARP is enabled
 +  Local Proxy ARP is disabled
 +  Security level is default
 +  Split horizon is enabled
 +  ICMP redirects are always sent
 +  ICMP unreachables are always sent
 +  ICMP mask replies are never sent
 +  IP fast switching is enabled
 +  IP Flow switching is disabled
 +  IP CEF switching is enabled
 +  IP CEF switching turbo vector
 +  IP Null turbo vector
 +  IP multicast fast switching is enabled
 +  IP multicast distributed fast switching is disabled
 +          ​
 +SW1(config)#​
 +*Mar  1 09:​11:​23.377:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/2
 +SW1(config)#​
 +*Mar  1 09:​13:​10.591:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/2
 +SW1(config)#​
 +*Mar  1 09:​13:​39.608:​ STP: VLAN0001 Topology Change rcvd on Fa1/0/2
 +SW1(config)#​
 +*Mar  1 09:​15:​30.245:​ STP: VLAN0001 heard root     ​1-0026.ca6b.e980 on Fa1/0/2
 +*Mar  1 09:​15:​30.245: ​    ​supersedes ​ 8193-e8ed.f315.9380
 +*Mar  1 09:​15:​30.245:​ STP: VLAN0001 new root is 1, 0026.ca6b.e980 on port Fa1/0/2, cost 38
 +SW1(config)#​
 +*Mar  1 09:​16:​59.475:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/2
 +SW1(config)#​
 +*Mar  1 09:​17:​00.557:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/2
 +SW1(config)#​
 +*Mar  1 09:​17:​02.562:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/2
 +SW1(config)#​
 +*Mar  1 09:​17:​04.567:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/2
 +SW1(config)#​
 +*Mar  1 09:​17:​06.571:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/2
 +SW1(config)#​conf t
 +             ^
 +% Invalid input detected at '​^'​ marker.
 +
 +SW1(config)#​spa
 +SW1(config)#​spanning-tree loop
 +SW1(config)#​spanning-tree loopguard defa
 +SW1(config)#​no spanning-tree loopguard default ​
 +SW1(config)#​spa
 +SW1(config)#​int range f1/0/1-2
 +SW1(config-if-range)#​spa
 +SW1(config-if-range)#​spanning-tree gu
 +SW1(config-if-range)#​spanning-tree guard lo
 +SW1(config-if-range)#​spanning-tree guard loop 
 +SW1(config-if-range)#​^Z
 +SW1#
 +*Mar  1 09:​21:​01.947:​ %SYS-5-CONFIG_I:​ Configured from console by console
 +SW1#sh spa
 +SW1#sh spanning-tree vlan 1
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   1
 +             ​Address ​    ​0026.ca6b.e980
 +             ​Cost ​       38
 +             ​Port ​       4 (FastEthernet1/​0/​2)
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   8193   ​(priority 8192 sys-id-ext 1)
 +             ​Address ​    ​e8ed.f315.9380
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  300 sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa1/​0/​1 ​            Desg FWD 19        128.3    P2p 
 +Fa1/​0/​2 ​            Root FWD 19        128.4    P2p 
 +
 +
 +SW1#
 +</​code>​
 +
 +<​code>​
 +SW2#conf t
 +Enter configuration commands, one per line.  End with CNTL/Z.
 +SW2(config)#​spa
 +SW2(config)#​spanning-tree loo
 +SW2(config)#​spanning-tree loopguard defa
 +SW2(config)#​spanning-tree loopguard default ​
 +SW2(config)#​spa
 +SW2(config)#​spanning-tree rootgu
 +SW2(config)#​spanning-tree rootgua
 +SW2(config)#​spanning-tree root   
 +SW2(config)#​spanning-tree roo 
 +SW2(config)#​spanning-tree roo
 +SW2(config)#​spanning-tree gua
 +SW2(config)#​spanning-tree por
 +SW2(config)#​spanning-tree portfast gur
 +SW2(config)#​spanning-tree portfast gua
 +SW2(config)#​spanning-tree portfast roo
 +SW2(config)#​spanning-tree portfast roogu
 +SW2(config)#​spanning-tree portfast ?    ​
 +  bpdufilter ​ Enable portfast bpdu filter on this switch
 +  bpduguard ​  ​Enable portfast bpdu guard on this switch
 +  default ​    ​Enable portfast by default on all access ports
 +
 +SW2(config)#​spanning-tree gu       
 +SW2(config)#​spanning-tree gur
 +SW2(config)#​spanning-tree gua
 +SW2(config)#​spanning-tree ro 
 +SW2(config)#​spanning-tree lo
 +SW2(config)#​spanning-tree lo
 +SW2(config)#​spanning-tree l 
 +SW2(config)#​spanning-tree loo
 +SW2(config)#​spanning-tree rootgu ​   ​
 +SW2(config)#​spanning-tree rootgu
 +SW2(config)#​spanning-tree rootgu
 +SW2(config)#​spanning-tree guard  ​
 +*Mar  1 08:​58:​10.553:​ set portid: VLAN0001 Fa1/0/1: new port id 8003
 +*Mar  1 08:​58:​10.553:​ STP: VLAN0001 Fa1/0/1 -> listening
 +SW2(config)#​spanning-tree guard loot
 +*Mar  1 08:​58:​12.549:​ %LINK-3-UPDOWN:​ Interface FastEthernet1/​0/​1,​ changed state to up
 +*Mar  1 08:​58:​13.556:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface FastEthernet1/​0/​1,​ changed state to up
 +SW2(config)#​spanning-tree guard root
 +                          ^
 +% Invalid input detected at '​^'​ marker.
 +
 +SW2(config)#​
 +*Mar  1 08:​58:​25.560:​ STP: VLAN0001 Fa1/0/1 -> learning
 +SW2(config)#​int f1/0/1
 +*Mar  1 08:​58:​40.567:​ STP[1]: Generating TC trap for port FastEthernet1/​0/​1
 +*Mar  1 08:​58:​40.567:​ STP: VLAN0001 sent Topology Change Notice on Fa1/0/2
 +*Mar  1 08:​58:​40.567:​ STP: VLAN0001 Fa1/0/1 -> forwarding
 +SW2(config)#​int f1/0/3
 +SW2(config-if)#​spa
 +SW2(config-if)#​spanning-tree gu
 +SW2(config-if)#​spanning-tree guard ro
 +SW2(config-if)#​spanning-tree guard root 
 +SW2(config-if)#​no spanning-tree guard root 
 +SW2(config-if)#​exit
 +SW2(config)#​no spa
 +SW2(config)#​no spanning-tree loop
 +SW2(config)#​no spanning-tree loopguard defau
 +SW2(config)#​no spanning-tree loopguard default ​
 +SW2(config)#​int f1/0/3
 +SW2(config-if)#​spa
 +SW2(config-if)#​spanning-tree gu
 +SW2(config-if)#​spanning-tree guard ro
 +SW2(config-if)#​spanning-tree guard root 
 +SW2(config-if)#​sp
 +SW2(config-if)#​spa
 +SW2(config-if)#​spanning-tree gua
 +SW2(config-if)#​spanning-tree guard loo
 +SW2(config-if)#​spanning-tree guard loop 
 +SW2(config-if)#​no spanning-tree guard loop 
 +SW2(config-if)#​^Z
 +SW2#
 +*Mar  1 09:​01:​11.788:​ %SYS-5-CONFIG_I:​ Configured from console by console
 +SW2#conf t
 +Enter configuration commands, one per line.  End with CNTL/Z.
 +SW2(config)#​spa
 +SW2(config)#​spa ​          
 +SW2(config)#​spanning-tree loop
 +SW2(config)#​spanning-tree loopguard defau
 +SW2(config)#​spanning-tree loopguard default ​
 +SW2(config)#​^Z
 +SW2#
 +*Mar  1 09:​01:​54.419:​ %SYS-5-CONFIG_I:​ Configured from console by console
 +SW2#
 +*Mar  1 09:​03:​51.029:​ STP: VLAN0001 sent Topology Change Notice on Fa1/0/2
 +*Mar  1 09:​03:​51.029:​ STP[1]: Generating TC trap for port FastEthernet1/​0/​1
 +*Mar  1 09:​03:​52.036:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface FastEthernet1/​0/​1,​ changed state to down
 +SW2#
 +*Mar  1 09:​03:​53.043:​ %LINK-3-UPDOWN:​ Interface FastEthernet1/​0/​1,​ changed state to down
 +SW2#
 +*Mar  1 09:​05:​42.917:​ set portid: VLAN0001 Fa1/0/1: new port id 8003
 +*Mar  1 09:​05:​42.917:​ STP: VLAN0001 Fa1/0/1 -> listening
 +SW2#
 +*Mar  1 09:​05:​44.913:​ %LINK-3-UPDOWN:​ Interface FastEthernet1/​0/​1,​ changed state to up
 +*Mar  1 09:​05:​45.920:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface FastEthernet1/​0/​1,​ changed state to up
 +SW2#
 +*Mar  1 09:​05:​57.924:​ STP: VLAN0001 Fa1/0/1 -> learning
 +SW2#
 +*Mar  1 09:​06:​12.931:​ STP[1]: Generating TC trap for port FastEthernet1/​0/​1
 +*Mar  1 09:​06:​12.931:​ STP: VLAN0001 sent Topology Change Notice on Fa1/0/2
 +*Mar  1 09:​06:​12.931:​ STP: VLAN0001 Fa1/0/1 -> forwarding
 +SW2#
 +*Mar  1 09:​15:​29.406:​ STP: VLAN0001 heard root     ​1-0026.ca6b.e980 on Fa1/0/1
 +*Mar  1 09:​15:​29.406: ​    ​supersedes ​ 8193-e8ed.f315.9380
 +*Mar  1 09:​15:​29.406:​ STP: VLAN0001 new root is 1, 0026.ca6b.e980 on port Fa1/0/1, cost 38
 +*Mar  1 09:​15:​29.842:​ STP: VLAN0001 sent Topology Change Notice on Fa1/0/1
 +*Mar  1 09:​15:​29.842:​ STP[1]: Generating TC trap for port FastEthernet1/​0/​2
 +*Mar  1 09:​15:​29.842:​ STP: VLAN0001 Fa1/0/2 -> blocking
 +SW2#
 +*Mar  1 09:​16:​58.636:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/1
 +SW2#
 +*Mar  1 09:​16:​59.718:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/1
 +SW2#
 +*Mar  1 09:​17:​01.723:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/1
 +SW2#
 +*Mar  1 09:​17:​03.728:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/1
 +SW2#
 +*Mar  1 09:​17:​05.733:​ STP: VLAN0001 heard root 32769-0022.bd89.2180 on Fa1/0/1
 +SW2#conf t
 +Enter configuration commands, one per line.  End with CNTL/Z.
 +SW2(config)#​spa
 +SW2(config)#​spanning-tree loop
 +SW2(config)#​spanning-tree loopguard defau
 +SW2(config)#​no spanning-tree loopguard default ​
 +SW2(config)#​int range f1/0/1-2
 +SW2(config-if-range)#​spa
 +SW2(config-if-range)#​spanning-tree gu
 +SW2(config-if-range)#​spanning-tree guard lo
 +SW2(config-if-range)#​spanning-tree guard loop 
 +SW2(config-if-range)#​^Z
 +SW2#
 +*Mar  1 09:​21:​02.082:​ %SYS-5-CONFIG_I:​ Configured from console by console
 +SW2#
 +</​code>​
 +
 +<​code>​
 +ASW1#sh spanning-tree ​
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   8193
 +             ​Address ​    ​e8ed.f315.9380
 +             ​Cost ​       19
 +             ​Port ​       1 (FastEthernet0/​1)
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   32769  (priority 32768 sys-id-ext 1)
 +             ​Address ​    ​0022.bd89.2180
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  300 sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa0/1               Root LRN 19        128.1    P2p 
 +Fa0/2               Altn BLK 19        128.2    P2p 
 +Fa0/3               Desg LIS 19        128.3    P2p 
 +Fa0/8               Desg LRN 19        128.8    P2p 
 +
 +
 +ASW1#sh spanning-tree ​
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   8193
 +             ​Address ​    ​e8ed.f315.9380
 +             ​Cost ​       19
 +             ​Port ​       1 (FastEthernet0/​1)
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   32769  (priority 32768 sys-id-ext 1)
 +             ​Address ​    ​0022.bd89.2180
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  15  sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa0/1               Root FWD 19        128.1    P2p 
 +Fa0/2               Altn BLK 19        128.2    P2p 
 +Fa0/3               Desg LIS 19        128.3    P2p 
 +Fa0/8               Desg FWD 19        128.8    P2p 
 +
 +
 +ASW1#conf t
 +Enter configuration commands, one per line.  End with CNTL/Z.
 +ASW1(config)#​spa
 +ASW1(config)#​spanning-tree loop
 +ASW1(config)#​spanning-tree loopguard defa
 +ASW1(config)#​spanning-tree loopguard default ​
 +ASW1(config)#​int f0/3
 +ASW1(config-if)#​swi
 +ASW1(config-if)#​spa ​       ​
 +ASW1(config-if)#​spanning-tree guar
 +ASW1(config-if)#​spanning-tree guard roo
 +ASW1(config-if)#​spanning-tree guard root 
 +ASW1(config-if)#​
 +*Mar  1 00:​02:​01.584:​ %SPANTREE-2-ROOTGUARD_CONFIG_CHANGE:​ Root guard enabled on port FastEthernet0/​3.
 +ASW1(config-if)#​
 +*Mar  1 00:​02:​27.631:​ %SPANTREE-2-ROOTGUARD_BLOCK:​ Root guard blocking port FastEthernet0/​3 on VLAN0001.
 +ASW1(config-if)#​sh sp
 +ASW1(config-if)#​^Z ​  
 +ASW1#sh spa
 +ASW1#sh spanning-tree ​
 +*Mar  1 00:​03:​39.764:​ %SYS-5-CONFIG_I:​ Configured from console by console
 +ASW1#sh spanning-tree inco
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#
 +*Mar  1 00:​03:​45.787:​ %SPANTREE-2-ROOTGUARD_UNBLOCK:​ Root guard unblocking port FastEthernet0/​3 on VLAN0001.
 +ASW1#                                   
 +*Mar  1 00:​06:​22.344:​ %SPANTREE-2-ROOTGUARD_BLOCK:​ Root guard blocking port FastEthernet0/​3 on VLAN0001.
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +VLAN0001 ​            ​FastEthernet0/​3 ​         Root Inconsistent
 +
 +Number of inconsistent ports (segments) in the system : 1
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +
 +Number of inconsistent ports (segments) in the system : 0
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +
 +Number of inconsistent ports (segments) in the system : 0
 +
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +
 +Number of inconsistent ports (segments) in the system : 0
 +
 +ASW1#
 +*Mar  1 00:​08:​08.569:​ %SPANTREE-2-ROOTGUARD_UNBLOCK:​ Root guard unblocking port FastEthernet0/​3 on VLAN0001.
 +ASW1#sh spanning-tree inconsistentports ​
 +
 +Name                 ​Interface ​               Inconsistency
 +-------------------- ------------------------ ------------------
 +
 +Number of inconsistent ports (segments) in the system : 0
 +
 +ASW1#conf t
 +Enter configuration commands, one per line.  End with CNTL/Z.
 +ASW1(config)#​int f0/3
 +ASW1(config-if)#​no spa
 +ASW1(config-if)#​no spanning-tree root
 +ASW1(config-if)#​no spanning-tree gua 
 +ASW1(config-if)#​no spanning-tree guard ro
 +ASW1(config-if)#​no spanning-tree rootgu  ​
 +ASW1(config-if)#​spa ​                   ​
 +ASW1(config-if)#​spanning-tree roo
 +ASW1(config-if)#​spanning-tree gua
 +ASW1(config-if)#​spanning-tree guard ro
 +ASW1(config-if)#​no spanning-tree guard root 
 +ASW1(config-if)#​
 +*Mar  1 00:​09:​18.295:​ %SPANTREE-2-ROOTGUARD_CONFIG_CHANGE:​ Root guard disabled on port FastEthernet0/​3.
 +ASW1(config-if)#​do sh spa
 +ASW1(config-if)#​do sh spanning-tree
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   1
 +             ​Address ​    ​0026.ca6b.e980
 +             ​Cost ​       19
 +             ​Port ​       3 (FastEthernet0/​3)
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   32769  (priority 32768 sys-id-ext 1)
 +             ​Address ​    ​0022.bd89.2180
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  15  sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa0/1               Desg FWD 19        128.1    P2p 
 +Fa0/2               Desg LRN 19        128.2    P2p 
 +Fa0/3               Root FWD 19        128.3    P2p 
 +Fa0/8               Desg FWD 19        128.8    P2p 
 +
 +
 +ASW1(config-if)#​do sh spanning-tree
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   1
 +             ​Address ​    ​0026.ca6b.e980
 +             ​Cost ​       19
 +             ​Port ​       3 (FastEthernet0/​3)
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   32769  (priority 32768 sys-id-ext 1)
 +             ​Address ​    ​0022.bd89.2180
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  15  sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa0/1               Desg FWD 19        128.1    P2p 
 +Fa0/2               Desg LRN 19        128.2    P2p 
 +Fa0/3               Root FWD 19        128.3    P2p 
 +Fa0/8               Desg FWD 19        128.8    P2p 
 +
 +
 +ASW1(config-if)#​do sh spanning-tree int f0/3 detail
 + Port 3 (FastEthernet0/​3) of VLAN0001 is root forwarding ​
 +   Port path cost 19, Port priority 128, Port Identifier 128.3.
 +   ​Designated root has priority 1, address 0026.ca6b.e980
 +   ​Designated bridge has priority 1, address 0026.ca6b.e980
 +   ​Designated port id is 128.1, designated path cost 0
 +   ​Timers:​ message age 1, forward delay 0, hold 0
 +   ​Number of transitions to forwarding state: 3
 +   Link type is point-to-point by default
 +   Loop guard is enabled by default on the port
 +   BPDU: sent 201, received 98
 +ASW1(config-if)#​do sh spanning-tree int f0/3 detail
 + Port 3 (FastEthernet0/​3) of VLAN0001 is root forwarding ​
 +   Port path cost 19, Port priority 128, Port Identifier 128.3.
 +   ​Designated root has priority 1, address 0026.ca6b.e980
 +   ​Designated bridge has priority 1, address 0026.ca6b.e980
 +   ​Designated port id is 128.1, designated path cost 0
 +   ​Timers:​ message age 2, forward delay 0, hold 0
 +   ​Number of transitions to forwarding state: 3
 +   Link type is point-to-point by default
 +   Loop guard is enabled by default on the port
 +   BPDU: sent 201, received 99
 +ASW1(config-if)#​do sh spanning-tree int f0/3 detail
 + Port 3 (FastEthernet0/​3) of VLAN0001 is root forwarding ​
 +   Port path cost 19, Port priority 128, Port Identifier 128.3.
 +   ​Designated root has priority 1, address 0026.ca6b.e980
 +   ​Designated bridge has priority 1, address 0026.ca6b.e980
 +   ​Designated port id is 128.1, designated path cost 0
 +   ​Timers:​ message age 2, forward delay 0, hold 0
 +   ​Number of transitions to forwarding state: 3
 +   Link type is point-to-point by default
 +   Loop guard is enabled by default on the port
 +   BPDU: sent 201, received 100
 +ASW1(config-if)#​do sh spanning-tree int f0/3 detail
 + Port 3 (FastEthernet0/​3) of VLAN0001 is root forwarding ​
 +   Port path cost 19, Port priority 128, Port Identifier 128.3.
 +   ​Designated root has priority 1, address 0026.ca6b.e980
 +   ​Designated bridge has priority 1, address 0026.ca6b.e980
 +   ​Designated port id is 128.1, designated path cost 0
 +   ​Timers:​ message age 1, forward delay 0, hold 0
 +   ​Number of transitions to forwarding state: 3
 +   Link type is point-to-point by default
 +   Loop guard is enabled by default on the port
 +   BPDU: sent 201, received 101
 +ASW1(config-if)#​do sh spanning-tree int f0/3 detail
 + Port 3 (FastEthernet0/​3) of VLAN0001 is root forwarding ​
 +   Port path cost 19, Port priority 128, Port Identifier 128.3.
 +   ​Designated root has priority 1, address 0026.ca6b.e980
 +   ​Designated bridge has priority 1, address 0026.ca6b.e980
 +   ​Designated port id is 128.1, designated path cost 0
 +   ​Timers:​ message age 2, forward delay 0, hold 0
 +   ​Number of transitions to forwarding state: 3
 +   Link type is point-to-point by default
 +   Loop guard is enabled by default on the port
 +   BPDU: sent 201, received 101
 +ASW1(config-if)#​do sh spanning-tree int f0/3 detail
 + Port 3 (FastEthernet0/​3) of VLAN0001 is root forwarding ​
 +   Port path cost 19, Port priority 128, Port Identifier 128.3.
 +   ​Designated root has priority 1, address 0026.ca6b.e980
 +   ​Designated bridge has priority 1, address 0026.ca6b.e980
 +   ​Designated port id is 128.1, designated path cost 0
 +   ​Timers:​ message age 2, forward delay 0, hold 0
 +   ​Number of transitions to forwarding state: 3
 +   Link type is point-to-point by default
 +   Loop guard is enabled by default on the port
 +   BPDU: sent 201, received 102
 +ASW1(config-if)#​do sh spanning-tree int f0/3 detail
 + Port 3 (FastEthernet0/​3) of VLAN0001 is root forwarding ​
 +   Port path cost 19, Port priority 128, Port Identifier 128.3.
 +   ​Designated root has priority 1, address 0026.ca6b.e980
 +   ​Designated bridge has priority 1, address 0026.ca6b.e980
 +   ​Designated port id is 128.1, designated path cost 0
 +   ​Timers:​ message age 1, forward delay 0, hold 0
 +   ​Number of transitions to forwarding state: 3
 +   Link type is point-to-point by default
 +   Loop guard is enabled by default on the port
 +   BPDU: sent 201, received 103
 +ASW1(config-if)#​do sh span
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   1
 +             ​Address ​    ​0026.ca6b.e980
 +             ​Cost ​       19
 +             ​Port ​       3 (FastEthernet0/​3)
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   32769  (priority 32768 sys-id-ext 1)
 +             ​Address ​    ​0022.bd89.2180
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  15  sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa0/1               Desg FWD 19        128.1    P2p 
 +Fa0/2               Desg FWD 19        128.2    P2p 
 +Fa0/3               Root FWD 19        128.3    P2p 
 +Fa0/8               Desg FWD 19        128.8    P2p 
 +
 +
 +ASW1(config-if)#​
 +*Mar  1 00:​11:​58.534:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface FastEthernet0/​3,​ changed state to down
 +ASW1(config-if)#​
 +*Mar  1 00:​11:​59.532:​ %LINK-3-UPDOWN:​ Interface FastEthernet0/​3,​ changed state to down
 +ASW1(config-if)#​
 +*Mar  1 00:​12:​05.732:​ %LINK-3-UPDOWN:​ Interface FastEthernet0/​3,​ changed state to up
 +*Mar  1 00:​12:​06.738:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface FastEthernet0/​3,​ changed state to up
 +ASW1(config-if)#​do sh spann
 +ASW1(config-if)#​do sh spann
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   1
 +             ​Address ​    ​0026.ca6b.e980
 +             ​Cost ​       19
 +             ​Port ​       3 (FastEthernet0/​3)
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   32769  (priority 32768 sys-id-ext 1)
 +             ​Address ​    ​0022.bd89.2180
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  15  sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa0/1               Desg FWD 19        128.1    P2p 
 +Fa0/2               Desg FWD 19        128.2    P2p 
 +Fa0/3               Root FWD 19        128.3    P2p 
 +Fa0/8               Desg FWD 19        128.8    P2p 
 +
 +
 +ASW1(config-if)#​conf t
 +                 ^
 +% Invalid input detected at '​^'​ marker.
 +
 +ASW1(config-if)#​exit
 +ASW1(config)#​spa
 +ASW1(config)#​spanning-tree loop
 +ASW1(config)#​spanning-tree loopguard defau
 +ASW1(config)#​spanning-tree loopguard default ​
 +ASW1(config)#​spa
 +ASW1(config)#​spa ​          
 +ASW1(config)#​int range f0/1-2 spa
 +ASW1(config)#​int range f0/​1-2 ​   ​
 +ASW1(config-if-range)#​spa
 +ASW1(config-if-range)#​spanning-tree gu  ​
 +ASW1(config-if-range)#​spanning-tree guard loo
 +ASW1(config-if-range)#​spanning-tree guard loop 
 +ASW1(config-if-range)#​^Z
 +ASW1#
 +*Mar  1 00:​15:​58.264:​ %SYS-5-CONFIG_I:​ Configured from console by console
 +ASW1#
 +</​code>​
 +
 +<​code>​
 +ASW2#conf t
 +Enter configuration commands, one per line.  End with CNTL/Z.
 +ASW2(config)#​
 +ASW2(config)#​
 +ASW2(config)#​
 +ASW2(config)#​
 +ASW2(config)#​
 +ASW2(config)#​
 +ASW2(config)#​
 +ASW2(config)#​spa
 +ASW2(config)#​spanning-tree pri
 +ASW2(config)#​spanning-tree vlan 1 pri
 +ASW2(config)#​spanning-tree vlan 1 priority 0
 +ASW2(config)#​int vlan 1
 +ASW2(config-if)#​ip address 172.16.0.22 255.255.255.0
 +ASW2(config-if)#​no shut
 +ASW2(config-if)#​e
 +*Mar  1 00:​03:​04.205:​ %LINK-3-UPDOWN:​ Interface Vlan1, changed state to up
 +ASW2(config-if)#​exit
 +ASW2(config)#​
 +*Mar  1 00:​03:​04.213:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface Vlan1, changed state to up
 +ASW2(config)#​spa
 +ASW2(config)#​spanning-tree vla
 +ASW2(config)#​spanning-tree vlan 1 pri
 +ASW2(config)#​no spanning-tree vlan 1 priority ​
 +ASW2(config)#​do sh spa                        ​
 +ASW2(config)#​do sh spanning-tree ​
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   8193
 +             ​Address ​    ​e8ed.f315.9380
 +             ​Cost ​       38
 +             ​Port ​       1 (FastEthernet0/​1)
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   32769  (priority 32768 sys-id-ext 1)
 +             ​Address ​    ​0026.ca6b.e980
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  15  sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa0/1               Root FWD 19        128.1    P2p 
 +
 +
 +ASW2(config)#​do sh spanning-tree int f0/1
 +
 +Vlan                Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +VLAN0001 ​           Root FWD 19        128.1    P2p 
 +ASW2(config)#​do sh spanning-tree int f0/1 deta
 + Port 1 (FastEthernet0/​1) of VLAN0001 is root forwarding ​
 +   Port path cost 19, Port priority 128, Port Identifier 128.1.
 +   ​Designated root has priority 8193, address e8ed.f315.9380
 +   ​Designated bridge has priority 32769, address 0022.bd89.2180
 +   ​Designated port id is 128.3, designated path cost 19
 +   ​Timers:​ message age 2, forward delay 0, hold 0
 +   ​Number of transitions to forwarding state: 1
 +   Link type is point-to-point by default
 +   BPDU: sent 33, received 67
 +ASW2(config)#​do sh spanning-tree int f0/1 deta
 + Port 1 (FastEthernet0/​1) of VLAN0001 is root forwarding ​
 +   Port path cost 19, Port priority 128, Port Identifier 128.1.
 +   ​Designated root has priority 8193, address e8ed.f315.9380
 +   ​Designated bridge has priority 32769, address 0022.bd89.2180
 +   ​Designated port id is 128.3, designated path cost 19
 +   ​Timers:​ message age 2, forward delay 0, hold 0
 +   ​Number of transitions to forwarding state: 1
 +   Link type is point-to-point by default
 +   BPDU: sent 33, received 68
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 33, received 71
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 33, received 71
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 33, received 71
 +ASW2(config)#​do ping 172.16.0.11
 +Type escape sequence to abort.
 +Sending 5, 100-byte ICMP Echos to 172.16.0.11,​ timeout is 2 seconds:
 +.!!!!
 +Success rate is 80 percent (4/5), round-trip min/avg/max = 1/2/8 ms
 +ASW2(config)#​do ping 172.16.0.11
 +Type escape sequence to abort.
 +Sending 5, 100-byte ICMP Echos to 172.16.0.11,​ timeout is 2 seconds:
 +!!!!!
 +Success rate is 100 percent (5/5), round-trip min/avg/max = 1/5/9 ms
 +ASW2(config)#​do ping 172.16.0.11 repeat 1000000
 +Type escape sequence to abort.
 +Sending 1000000, 100-byte ICMP Echos to 172.16.0.11,​ timeout is 2 seconds:
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!.
 +Success rate is 99 percent (912/913), round-trip min/avg/max = 1/3/33 ms
 +ASW2(config)#​spa
 +ASW2(config)#​spanning-tree vla
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 33, received 117
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 33, received 119
 +ASW2(config)#​spa ​                                      
 +ASW2(config)#​spanning-tree vla
 +ASW2(config)#​spanning-tree vlan 1 pri
 +ASW2(config)#​spanning-tree vlan 1 priority 0
 +ASW2(config)#​spanning-tree vlan 1 priority 0
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 34, received 125
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 35, received 125
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 35, received 125
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 49, received 125
 +ASW2(config)#​do sh spanning-tree int f0/1 deta | i BPDU
 +   BPDU: sent 49, received 125
 +ASW2(config)#​sh spa
 +ASW2(config)#​sh spann
 +ASW2(config)#​do sh spa
 +ASW2(config)#​do sh spanning-tree ​
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   1
 +             ​Address ​    ​0026.ca6b.e980
 +             This bridge is the root
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   1      (priority 0 sys-id-ext 1)
 +             ​Address ​    ​0026.ca6b.e980
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  300 sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa0/1               Desg FWD 19        128.1    P2p 
 +
 +
 +ASW2(config)#​do ping 172.16.0.11 repeat 1000000 ​       ​
 +Type escape sequence to abort.
 +Sending 1000000, 100-byte ICMP Echos to 172.16.0.11,​ timeout is 2 seconds:
 +......
 +Success rate is 0 percent (0/6)
 +ASW2(config)#​no spa
 +ASW2(config)#​no spanning-tree vla
 +ASW2(config)#​no spanning-tree vlan 1 pri
 +ASW2(config)#​no spanning-tree vlan 1 priority ​
 +ASW2(config)#​do ping 172.16.0.11 repeat 1000000
 +Type escape sequence to abort.
 +Sending 1000000, 100-byte ICMP Echos to 172.16.0.11,​ timeout is 2 seconds:
 +........................!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.
 +Success rate is 95 percent (570/595), round-trip min/avg/max = 1/3/33 ms
 +ASW2(config)#​do ping 172.16.0.11 repeat 1000000
 +Type escape sequence to abort.
 +Sending 1000000, 100-byte ICMP Echos to 172.16.0.11,​ timeout is 2 seconds:
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +Success rate is 100 percent (804/804), round-trip min/avg/max = 1/4/42 ms
 +ASW2(config)#​sh spa                            ​
 +ASW2(config)#​spa ​  
 +ASW2(config)#​spanning-tree vlan 1 pri
 +ASW2(config)#​spanning-tree vlan 1 priority 0
 +ASW2(config)#​
 +*Mar  1 00:​11:​41.027:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface Vlan1, changed state to down
 +*Mar  1 00:​11:​42.025:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface FastEthernet0/​1,​ changed state to down
 +ASW2(config)#​
 +*Mar  1 00:​11:​43.024:​ %LINK-3-UPDOWN:​ Interface FastEthernet0/​1,​ changed state to down
 +ASW2(config)#​
 +*Mar  1 00:​11:​49.256:​ %LINK-3-UPDOWN:​ Interface FastEthernet0/​1,​ changed state to up
 +*Mar  1 00:​11:​50.263:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface FastEthernet0/​1,​ changed state to up
 +ASW2(config)#​^Z
 +ASW2#sh spa
 +ASW2#sh spanning-tree ​
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   1
 +             ​Address ​    ​0026.ca6b.e980
 +             This bridge is the root
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   1      (priority 0 sys-id-ext 1)
 +             ​Address ​    ​0026.ca6b.e980
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  15  sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +-------------------
 +*Mar  1 00:12:13.43 ---- --- --------- -------- --------------------------------
 +Fa0/1               Desg LRN 19        128.1    P2p 
 +
 +
 +ASW2#2: %SYS-5-CONFIG_I:​ Configured from console by console
 +ASW2#
 +*Mar  1 00:​12:​17.274:​ %LINEPROTO-5-UPDOWN:​ Line protocol on Interface Vlan1, changed state to up
 +ASW2#conf t
 +Enter configuration commands, one per line.  End with CNTL/Z.
 +ASW2(config)#​do sh spa
 +ASW2(config)#​do sh spanning-tree ​
 +
 +VLAN0001
 +  Spanning tree enabled protocol ieee
 +  Root ID    Priority ​   1
 +             ​Address ​    ​0026.ca6b.e980
 +             This bridge is the root
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +
 +  Bridge ID  Priority ​   1      (priority 0 sys-id-ext 1)
 +             ​Address ​    ​0026.ca6b.e980
 +             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
 +             Aging Time  300 sec
 +
 +Interface ​          Role Sts Cost      Prio.Nbr Type
 +------------------- ---- --- --------- -------- --------------------------------
 +Fa0/1               Desg FWD 19        128.1    P2p 
 +
 +
 +ASW2(config)#​do ping 172.16.0.11 repeat 10000
 +Type escape sequence to abort.
 +Sending 10000, 100-byte ICMP Echos to 172.16.0.11,​ timeout is 2 seconds:
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 +!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.
 +Success rate is 99 percent (893/894), round-trip min/avg/max = 1/5/1007 ms
 +ASW2(config)#​
 +</​code>​
 +
 +===== References =====
 +
 +  - [[https://​www.infraexpert.com/​study/​stpz14.html|STPの拡張技術 - ループガード]]
  
tech/network/cisco/stp/loopguard/loopguard.txt · Last modified: 2019/06/08 07:09 by wnoguchi