Reference Guide

Parameters
● management—Enter the keyword management to display information corresponding to the
management VRF instance.
● vrf-name—Enter the name of the non-default VRF instance to display information corresponding to
that VRF instance.
Default Not configured
Command Mode EXEC
Usage
Information
None
Example
OS10# show ip vrf
VRF-Name Interfaces
default Mgmt1/1/1
Eth1/1/1-1/1/2
Vlan1
management
OS10# show ip vrf management
VRF-Name Interfaces
management
Supported
Releases
10.4.0E(R1) or later
Bidirectional Forwarding Detection
The Bidirectional Forwarding Detection (BFD) protocol rapidly detects communication failures between two adjacent routers.
BFD is a simple and lightweight replacement for link-state detection mechanisms in existing routing protocols. It also provides a
failure detection solution for links with no routing protocol.
BFD provides forwarding-path failure detection that is performed in milliseconds, instead of seconds, as with routing protocol
hello packets. Because BFD is independent of routing protocols, it provides consistent failure detection in a network. BFD
eliminates multiple protocol-dependent timers and methods. Networks converge faster because BFD triggers link-state changes
in the routing protocol sooner and more consistently.
BFD operates as a simple hello mechanism. Two neighboring routers running BFD establish a session using a three-way
handshake. After the session is established, the routers exchange periodic control packets at sub-second intervals. If a router
does not receive a hello packet within a specified time, routing protocols are notified that the forwarding path is down.
In addition, BFD sends a control packet when there is a state change or change in a session parameter. These control packets
are sent without regard to transmit and receive intervals in a routing protocol.
BFD is an independent and generic protocol, which all media, topologies, and routing protocols can support using any
encapsulation. OS10 implements BFD at Layer 3 (L3) and with User Datagram Protocol (UDP) encapsulation. BFD is supported
for static and dynamic routing protocols, such as VRRP, OSPF, OSPFv3, IS-IS, and BGP.
NOTE: In this release, BFD is only supported for BGP.
BFD session states
To establish a BFD session between two routers, enable BFD on both sides of the link. BFD routers can operate in both active
and passive roles.
● The active router starts the BFD session. Both routers can be active in the same session.
● The passive router does not start a session. It only responds to a request for session initialization from the active router.
A BFD session can occur in Asynchronous and Demand modes. OS10 BFD supports only Asynchronous mode.
● In Asynchronous mode, both systems send periodic control messages at a specified interval to indicate that their session
status is Up.
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Layer 3