Hello everyone,
Today I will share with you the differences between the internal and external preferences of a router.
Routers define external preference and internal preference. Value 0 indicates direct routes and value 255 indicates routes learned from unreliable sources. A smaller value indicates a higher preference. External preferences are manually configured for routing protocols. Table 1 lists the default external preferences of routing protocols.
Routing Protocol or Route Type | Default External Preference |
|---|---|
Direct | 0 |
OSPF | 10 |
IS-IS | 15 |
Static | 60 |
RIP | 100 |
OSPF ASE | 150 |
OSPF NSSA | 150 |
IBGP | 255 |
EBGP | 255 |
During route selection, the device first compares the external preferences of routes. When the same external preference is set for different routing protocols, the device selects the optimal route based on the internal preference. Internal preferences of routing protocols cannot be manually configured. Table 2 lists the internal preferences of routing protocols.
Routing Protocol or Route Type | Internal Preference |
|---|---|
Direct | 0 |
OSPF | 10 |
IS-IS Level-1 | 15 |
IS-IS Level-2 | 18 |
Static | 60 |
RIP | 100 |
OSPF ASE | 150 |
OSPF NSSA | 150 |
IBGP | 200 |
EBGP | 20 |
That is all I want to share with you! Thank you!
