Dell BigIron RX Series, Configuration Manual

Page: 847 / 1458

BigIron RX Series Configuration Guide 771
53-1002253-01
Configuring BGP4 neighbors
26
By default, load sharing applies to EBGP and IBGP paths, and does not apply to paths from
different neighboring ASs.
Configuring BGP4 neighbors
The BGP4 protocol does not contain a peer discovery process. Therefore, for each of the router’s
BGP4 neighbors (peers), you must indicate the neighbor’s IP address and the AS each neighbor is
in. Neighbors that are in different ASs communicate using EBGP. Neighbors within the same AS
communicate using IBGP.
NOTE
If the BigIron RX has multiple neighbors with similar attributes, you can simplify configuration by
configuring a peer group, then adding individual neighbors to it. The configuration steps are similar,
except you specify a peer group name instead of a neighbor IP address when configuring the
neighbor parameters, then add individual neighbors to the peer group. Refer to
“Configuring a BGP4
peer group” on page 778.
NOTE
The BigIron RX attempts to establish a BGP4 session with a neighbor as soon as you enter a
command specifying the neighbor’s IP address. If you want to completely configure the neighbor
parameters before the device establishes a session with the neighbor, you can administratively shut
down the neighbor. Refer to
“Administratively shutting down a session with a BGP4 neighbor” on
page 781.
NOTE
When a route-map, prefix-list, or as-path ACL is modified, BGP will be notified. Outbound route
polices will be updated automatically. No longer requires user to manually clear neighbor
soft-outbound. If the filter is used by BGP inbound route policies, a manual clear of a neighbor is still
required.
To add a BGP4 neighbor with IP address 209.157.22.26 remote-as 100, enter the following
command.
BigIron RX(config-bgp)# neighbor 209.157.22.26 remote-as 100
The neighbor’s <ip-addr> must be a valid IP address.
The neighbor command has some additional parameters, as shown in the following syntax.
Syntax: [no] neighbor <ip-addr> | <peer-group-name>
[advertisement-interval <num> ]
[capability orf prefixlist [send | receive]]
[default-originate [route-map
<map-name> ]]
[description <string> ]
[distribute-list in | out <num,num,...> | <acl-num> in | out]
[ebgp-multihop [ <num> ]]
[filter-list in | out <num,num,...> | <acl-num> in | out | weight]
[maximum-prefix <num> [<threshold> ] [teardown]]
[next-hop-self]
[password [0 | 1]
<string> ]
[prefix-list <string> in | out]
[remote-as <as-number> ]