BGP Attributes

BGP Attributes 

How BGP Findes The Best Path ? 

0. Ignore routes with an inaccessible next hop address.

1. Prefer the path with the higest WEIGHT. (By Default is 0)

2. Prefer the path with the higest LOCAL_PREF.(By Default is 100)

3. Prefer the path that was locally originate via a network command.

4. Prefer the path with the shortest AS_PATH. (AS Hop Count)

5. Prefer the path with the lowest origin type. (i > E > ?)

6. Prefer the path with the lowest multi-exit discriminator. (MED)

7. Prefer eBGP over iBGP paths.

8. Prefer the path with the lowest IGP metric to the BGP next hop.

9. Determine if multiple paths require installation in the routing table for BGP Multipath.

10. When both paths are external, prefer the path that was recived first. (the oldest one)

11. Prefer the route that comes from the BGP router with the lowest router ID.

12. If originator or router ID is the same for multiple paths, prefer the path with the minimum cluster list length.

13. Prefer the path that comes from the lowest neighbor address.

1. Weight (Bigger is better)
2. Local preference (Bigger is better)
3. Self originated (Locally injected is better than iBGP/eBGP learned)
4. AS-Path (Smaller is better)
5. Origin (Prefer ORIGIN code I over E, and E over ?)
6. MED (Smaller is better)
7. External (Prefer eBGP over iBGP)
8. IGP cost (Smaller is better)
9. EBGP Peering (Older is better)
10. RID (Lower is better)

##########################################################################################################