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Network Next Hop Metric LocPrf Weight Path
*> 7.0.0.0/29 10.114.8.33 0 0 18508 ?
*> 7.0.0.0/30 10.114.8.33 0 0 18508 ?
*> 9.2.0.0/16 10.114.8.33 10 0 18508 701 i
AS Path
The AS path is the list of all ASs that all the prefixes listed in the update have passed through.
The BGP speaker adds the local AS number when advertising to a eBGP neighbor.
NOTE: Any update that contains the AS path number 0 is valid.
The AS path is shown in the following example. The origin attribute is shown following the AS path information (shown in bold).
Example of Viewing AS Paths
Dell#show ip bgp paths
Total 30655 Paths
Address Hash Refcount Metric Path
0x4014154 0 3 18508 701 3549 19421 i
0x4013914 0 3 18508 701 7018 14990 i
0x5166d6c 0 3 18508 209 4637 1221 9249 9249 i
0x5e62df4 0 2 18508 701 17302 i
0x3a1814c 0 26 18508 209 22291 i
0x567ea9c 0 75 18508 209 3356 2529 i
0x6cc1294 0 2 18508 209 1239 19265 i
0x6cc18d4 0 1 18508 701 2914 4713 17935 i
0x5982e44 0 162 18508 209 i
0x67d4a14 0 2 18508 701 19878 ?
0x559972c 0 31 18508 209 18756 i
0x59cd3b4 0 2 18508 209 7018 15227 i
0x7128114 0 10 18508 209 3356 13845 i
0x536a914 0 3 18508 209 701 6347 7781 i
0x2ffe884 0 1 18508 701 3561 9116 21350 i
Next Hop
The next hop is the IP address used to reach the advertising router.
For EBGP neighbors, the Next-Hop address is the IP address of the connection between the neighbors. For IBGP, the EBGP
Next-Hop address is carried into the local AS. A Next Hop attribute is set when a BGP speaker advertises itself to another BGP
speaker outside its local AS. It can also be set when advertising routes within an AS. The Next Hop attribute also serves as a
way to direct traffic to another BGP speaker, rather than waiting for a speaker to advertise.
Dell Networking OS allows you to set the Next Hop attribute in the CLI. Setting the Next Hop attribute lets you determine a
router as the next hop for a BGP neighbor.
Multiprotocol BGP
Multiprotocol extensions for BGP (MBGP) are defined in IETF RFC 2858. MBGP allows different types of address families to be
distributed in parallel.
MBGP allows information about the topology of the IP multicast-capable routers to be exchanged separately from the topology
of normal IPv4 and IPv6 unicast routers. It allows a multicast routing topology different from the unicast routing topology.
NOTE:
It is possible to configure BGP peers that exchange both unicast and multicast network layer reachability
information (NLRI), but you cannot connect multiprotocol BGP with BGP. Therefore, you cannot redistribute multiprotocol
BGP routes into BGP.
Border Gateway Protocol IPv4 (BGPv4) 163