Configuring a route reflector, Enabling or disabling comparison of the router ids, Configuring confederations – Brocade BigIron RX Series Configuration Guide User Manual
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BigIron RX Series Configuration Guide
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Configuring a route reflector
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Configuring a route reflector
You can configure one cluster ID on the router. All route-reflector clients for the router are members
of the cluster.
To configure a device as route reflector 1, enter the following command.
BigIron RX(config-bgp)# cluster-id 1
Syntax: [no] cluster-id <num> | <ip-addr>
The <num> | <ip-addr> parameter specifies the cluster ID (1 – 4294967295) or an IP address.
The default is the router ID.
NOTE
If the cluster contains more than one route reflector, you need to configure the same cluster ID on
all the route reflectors in the cluster. The cluster ID helps route reflectors avoid loops within the
cluster.
Enabling or disabling comparison of the router IDs
Router ID comparison is
in the algorithm BGP4 uses to select the next path for a route.
NOTE
Comparison of router IDs is applicable only when BGP4 load sharing is disabled.
When router ID comparison is enabled, the path comparison algorithm compares the router IDs of
the neighbors that sent the otherwise equal paths.
•
If BGP4 load sharing is disabled (maximum-paths 1), the device selects the path that came
from the neighbor with the lower router ID.
•
If BGP4 load sharing is enabled, the device load shares among the remaining paths. In this
case, the router ID is not used to select a path.
NOTE
Router ID comparison is disabled by default.
To enable router ID comparison, enter the following command at the BGP configuration level of the
CLI.
BigIron RX(config-bgp)# compare-routerid
Syntax: [no] compare-routerid
For more information, refer to
“How BGP4 selects a path for a route”
Configuring confederations
A confederation is a BGP4 Autonomous System (AS) that has been subdivided into multiple,
smaller ASs. Subdividing an AS into smaller ASs simplifies administration and reduces BGP-related
traffic, thus reducing the complexity of the Interior Border Gateway Protocol (IBGP) mesh among
the BGP routers in the AS.