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# When the link between Switch B and the Layer-2 switch fails, BFD can quickly detect the failure.
#Aug 8 14:54:05:362 2009 SwitchA IFNET/4/INTERFACE UPDOWN:
Trap 1.3.6.1.6.3.1.1.5.3<linkDown>: Interface 983041 is Down, ifAdminStatus is
1, ifOperStatus is 2
#Aug 8 14:54:05:363 2009 SwitchA ISIS/4/ADJ_CHANGE:TrapID(1.3.6.1.2.1.138.0.17<
isisAdjacencyChange>), ISIS Level-2 Adjencency IN Circuit-983041 State Change.
#Aug 8 14:54:05:364 2009 SwitchA ISIS/4/ADJ_CHANGE:TrapID(1.3.6.1.2.1.138.0.17<
isisAdjacencyChange>), ISIS Level-1 Adjencency IN Circuit-983041 State Change.
%Aug 8 14:54:05:365 2009 SwitchA IFNET/4/LINK UPDOWN: vlan10: link status is DOWN
%Aug 8 14:54:05:366 2009 SwitchA IFNET/4/UPDOWN: Line protocol on the interface Vlan10
is DOWN
%Aug 8 14:54:05:367 2009 SwitchA ISIS/4/ADJLOG:ISIS-1-ADJCHANGE: Adjacency To
0000.0000.0002 (vlan10) DOWN, Level-2 Circuit Down.
%Aug 8 14:54:05:367 2009 SwitchA ISIS/4/ADJLOG:ISIS-1-ADJCHANGE: Adjacency To
0000.0000.0002 (vlan10) DOWN, Level-2 Adjacency clear.
%Aug 8 14:54:05:368 2009 SwitchA ISIS/4/ADJLOG:ISIS-1-ADJCHANGE: Adjacency To
0000.0000.0002 (vlan10) DOWN, Level-1 Circuit Down.
%Aug 8 14:54:05:369 2009 SwitchA ISIS/4/ADJLOG:ISIS-1-ADJCHANGE: Adjacency To
0000.0000.0002 (vlan10) DOWN, Level-1 Adjacency clear.
*Aug 8 14:54:05:369 2009 SwitchA ISIS/6/ISIS: ISIS-1-BFD: Recieve BFD session down . Type
0. DstIPAddr: FE80::20F:FF:FE00:1200 , SrcIPAddr: FE80::20F:FF:FE00:1202
*Aug 8 14:54:05:370 2009 SwitchA ISIS/6/ISIS: ISIS-1-BFD: Success to send msg. Msg type
1 delete session. IfPhyIndex: 5 , DstIPAddr: FE80::20F:FF:FE00:1200 , SrcIPAddr:
FE80::20F:FF:FE00:1202. NeighborType:Level-1.
# Display the BFD information of Switch A. You can see that Switch A has removed its neighbor
relationship with Switch B and therefore no information is output.
<SwitchA> display bfd session
# Display route 2001:4::0/64 on Switch A, and you can see that Switch A and Switch B communicate
through Switch C.
<SwitchA> display ipv6 routing-table 2001:4::0 64 verbose
Routing Table :
Summary Count : 1
Destination : 2001:4::0 PrefixLength : 64
NextHop : 2001:2::2 Preference : 15
IpPrecedence : QosLcId :
RelayNextHop : :: Tag : 0H
Neighbor : :: ProcessID : 0
Interface : Vlan-interface11 Protocol : ISISv6
State : Invalid Adv Cost : 30
Tunnel ID : 0x0 Label : NULL
Age : 4610sec