BFD Bidirectional Detection Technology
BFD is a protocol for mechanisms to diffuse hello, he was a bit different from the ip-link, ip-link is a tool used in other agreements, and BFD has its own agreement
BFD may be static routing, dynamic routing, policy routing, and the hot standby linkage dhcp
principle:
BFD will not establish a neighbor, so when the dynamic routing protocol to establish the neighbors, BFD will create a session-based routing protocol neighbor relationship
such as ospf, when a link fails, the chain can be directly connected to perceive at once, but it would not be able indirect link fast perception as to ospf been to 4 times the hello time before determination that failure
BFD session can be specified, before ospf detect the fault and notify ospf, it updates the routing table does not affect normal service performed
when a link fault is removed, BFD will notify ospf failure to lift, routing table updates
Configuration:
Beginning with: the ip and regional policy, as well as routing protocols
Dynamic routing:
In the system view: bfd (open BFD)
in view ospf protocol: bfd all-interfaces enable (linkage)
Static Routing:
Use the peer-A2B the bind ID BFD 12.1.1.2 interface G1 / 0 /. 1
Discriminator 100 local
Discriminator can remort 200 is (this peer end is a mirror image relationship, must match)
the Commit (submitted)
BFD B2a interface 12.1.1.1 the bind ID Use the peer-G1 / 0 /. 1
Discriminator 200 is local
Discriminator remort100
the commit
There is a bfd session id, 1--8191 static routing id. From the beginning of 8192 is a dynamic
checking mechanism bfd packets sent
