Connectivity Guide

Changing OSPFv3 session parameters
Configure BFD sessions with default intervals and a default role.
The parameters that you can configure are: desired tx interval, required min rx interval, detection multiplier, and system role.
Configure these parameters for all OSPFv3 sessions or all OSPFv3 sessions on a particular interface. If you change a parameter
globally, the change affects all OSPFv3 neighbors sessions. If you change a parameter at the interface level, the change affects
all OSPF sessions on that interface.
NOTE: By default, OSPF uses the following BFD parameters for it's neighbors: min_tx = 200 msec, min_rx = 200 msec,
multiplier = 3, role = active. If BFD is configured under interface context, that will be given high priority.
To change parameters for all OSPFv3 sessions or for OSPF sessions on a single interface, use the following commands:
1. Change parameters for OSPF sessions.
bfd all-neighbors interval milliseconds min_rx milliseconds multiplier value role [active
| passive]
ROUTER-OSPFv3 Mode
2. Change parameters for all OSPF sessions on an interface.
ipv6 ospf bfd all-neighbors interval milliseconds min_rx milliseconds multiplier value
role [active | passive]
INTERFACE CONFIGURATION Mode
Disabling BFD for OSPFv3
If you disable BFD globally, all sessions are torn down and sessions on the remote system are placed in a Down state. If you
disable BFD on an interface, sessions on the interface are torn down and sessions on the remote system are placed in a
Down state. Disabling BFD does not trigger a change in BFD clients; a final Admin Down packet is sent before the session is
terminated.
To disable BFD sessions, use the following commands:
1. Disable BFD sessions with all OSPF neighbors.
no bfd all-neighbors
ROUTER-OSPFv3 Mode
2. Disable BFD sessions with all OSPF neighbors on an interface.
ipv6 ospf bfd all-neighbors disable
INTERFACE CONFIGURATION Mode
To re-enable BFD, disabled the interface alone using the following commands:
● no ipv6 ospf bfd all-neighbors command
● ipv6 ospf bfd all-neighbors
BFD for Static route
The static Route BFD feature enables association of static routes with a BFD session in order to monitor the static route
reachability. Depending on the status of the BFD session the static routes are added to or removed from the Routing
Information Base (RIB). When BFD is configured, the nexthop reachability is dependent on the BFD state of the BFD session
corresponding to the specified next hop. If the BFD session of the configured nexthop is down the static route will not be
installed in the RIB.
The BFD session needs to be established successfully for the static route. BFD must be configured on both the peers pointing to
its neighbor as next hop. There is no dependency on the order of configuration of static route and BFD configuration. The user
has provision to configure BFD for all the static routes configured or for none of the static routes. Both IPv4 and IPv6 static
route BFD is supported.
NOTE:
You can configure BFD for all the static routes. Meaning, there is no provision for configuring BFD only for some of
the existing static routes.
Configuring BFD for static routes is a three-step process:
1. Enable BFD Globally.
Layer 3
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