•
Advertise Default Route
22
– The router can advertise a default external route into
the autonomous system (AS). (Options: NotAlways, Always; Defaul t: NotAlwa ys)
• Always – The router will ad verti se itse lf as a defau lt e xter nal r oute f or th e local
AS, even if a default external route does not actuall y exist. (To d efine a defa ult
route, see “Configuring Static Routes” on page 19-21.)
• NotAlways – It can only advertise a default external route into the AS if it has
been configured to import external routes through RIP or static routes, and such
a route is known. (See “Redistributing External Routes” on page 20-35.)
• External Metric Type22 – The external lin k type u sed to a dver tise t he defau lt
route. Type 1 route advertisements add the inter nal cost to the external ro ute
metric. Type 2 routes do not add the internal cost metric. When compar ing Ty pe 2
routes, the internal cost is only used as a tie-breaker if sev era l Ty pe 2 ro ute s have
the same cost. (Default: Type 2)
• Default External Metric22 – The Metric assigned to the default ro ute.
(Range: 1-65535; Default: 10)
The metric for the default external route is used to calculate the path cost for traffic
passed from other routers within the AS out through the ASBR.
20-17
Configuring the Open Shortest Path First Protocol
20