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Use the no version to remove the static route from the routing table and thereby
remove BFD from that static route.
See ip route
How RTR Next-Hop Verification Works
Static routes on E Series routers can use Response Time Reporter (RTR) probes
configured as echo (ping) types to verify the availability of the next hop and obtain
the state of the IP service. For more information about using RTR, see "Response
Time Reporter" on page 65.
If you specify the verify rtr keywords with an RTR operation number when you issue
the ip route command to establish a static route, the router verifies the next-hop
status and installs the static route in the routing table only if both of the following
conditions are met:
The next hop to the specified IP destination address is resolved.
The specified RTR operation is currently reachable.
You can further control the installation of static routes by specifying the last-resort
keyword, which is valid only when you use the verify rtr keywords in the ip route
command. The last-resort keyword instructs the router to install the static route in
the routing table even if the specified RTR operation is unreachable, provided that
no other static route to the same network prefix is available.
Although the configuration example in the next section uses Fast Ethernet interfaces,
E Series routers support next-hop verification on any type of lower-layer interface.
RTR Configuration Example
Figure 12 on page 34 shows a sample configuration that illustrates the next-hop
verification feature. In this example, two Fast Ethernet interfaces are configured
between a remote system and an E Series router: Fast Ethernet interface 4/0 and
Fast Ethernet interface 4/1. At any given time, only one of these interfaces forwards
IP traffic, even though the associated layer 2 interfaces may be up concurrently.
On the E Series router, Fast Ethernet interfaces 4/0 and 4/1 are configured as
unnumbered IP interfaces. In addition, each interface has an RTR probe configured
as an echo type that sends requests over the interface to determine its availability.
RTR 10 sends requests over Fast Ethernet interface 4/0, and RTR 11 sends requests
over Fast Ethernet interface 4/1.
In this example, both RTR 10 and RTR 11 use the IP address of the remote system
(10.1.1.2) as the target address. When you configure multiple RTR entries to use the
same target address, you must set the receive-interface attribute to specify the
interface on which the probe expects to receive responses. (See Step 4c in the next
section, "Configuring RTR Next-Hop Verification" on page 34.) This action enables
the router to map incoming responses to the proper RTR entry, even when multiple
RTR entries have the same target address.
Chapter 1: Configuring IP
33
IP Routing
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