Origin - Dell Force10 Z9000 Configuration Manual

Figure 8-6. MED Route Example
AS 100
Note: With FTOS Release 8.3.1.0, configuring the set metric-type internal command in a route-map
advertises the IGP cost as MED to outbound EBGP peers when redistributing routes. The configured set
metric value overwrites the default IGP cost. If the outbound route-map uses MED, it will overwrite the
IGP MED.

Origin

The Origin indicates the origin of the prefix, or how the prefix came into BGP. There are three Origin
codes: IGP, EGP, INCOMPLETE.
• IGP indicated the prefix originated from information learned through an interior gateway protocol.
• EGP indicated the prefix originated from information learned from an EGP protocol, which NGP
replaced.
• INCOMPLETE indicates that the prefix originated from an unknown source.
Generally, an IGP indicator means that the route was derived inside the originating AS. EGP generally
means that a route was learned from an external gateway protocol. An INCOMPLETE origin code
generally results from aggregation, redistribution or other indirect ways of installing routes into BGP.
In FTOS, these origin codes appear as shown in
of INCOMPLETE. The lower case letter (i) indicates an Origin code of IGP.
| Border Gateway Protocol
170
Router A
Router B
OC3 Link
Set MED to 50
Set MED to 100
T1 Link
Router C
Router D
Figure 8-7. The question mark (?) indicates an Origin code
AS 200
Router E