Configuring Default Routes - Juniper IGP - CONFIGURATION GUIDE V11.1.X Configuration Manual

Configuring Default Routes

You can specify a default route within IS-IS routing domains. You can also suppress
the installation of a default route to level 1-2 routers by level 1 routers.
Optionally, when you issue the default-information originate command and specify
a route map, you can use the map to set a route tag for the default route. Make sure
the route map you specify includes the set tag command, which defines a tag value
for the default route within the IS-IS domain. For details about configuring and using
route maps, see JUNOSe IP Services Configuration Guide.
default-information originate
suppress-default
Select a value in the range 1–255. A value of 255 means discard the route.
Example
host1(config-router)#distance ip 50
Use the no version to restore the default value, 115.
See distance ip
Use to generate a default route into an IS-IS routing domain.
When you specify a route map with this command and the router has a route
to 0.0.0.0 in the routing table, IS-IS originates an advertisement for 0.0.0.0 in
its LSPs.
When you do not specify a route map, the default route is advertised only in
level 2 LSPs.
If you specify a route map, you can use the map to set a route tag for the default
route.
For level 1 routing, look for the closest level 1-2 router to find the default route.
The closest level 1-2 router is found by looking at the attach bit (ATT) in level 1
LSPs.
The default value is disabled.
Example1
host1(config-router)#default-information originate
Example 2
host1(config-router)#default-information originate route-map map3
Use the no version to disable the command.
See default-information originate
Chapter 6: Configuring IS-IS
Configuring Global IS-IS Parameters
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