Default Redistribution And Route Aggregation Example - IBM RackSwitch G8000 Application Manual

Default Redistribution and Route Aggregation Example

254
RackSwitch G8000: Application Guide
2. Define the IP interfaces with IPv4 addresses.
The switch will need an IP interface for each default gateway to which it will be
connected. Each interface must be placed in the appropriate VLAN. These
interfaces will be used as the primary and secondary default gateways for the
switch.
>> # interface ip 1
>> (config-ip-if)# ip address 200.200.200.1
>> (config-ip-if)# ip netmask 255.255.255.0
>> (config-ip-if)# enable
>> (config-ip-if)# exit
>> # interface ip 2
>> (config-ip-if)# ip address 210.210.210.1
>> (config-ip-if)# ip netmask 255.255.255.0
>> (config-ip-if)# enable
>> (config-ip-if)# exit
3. Enable IP forwarding.
IP forwarding is turned on by default and is used for VLAN-to-VLAN (non-BGP)
routing. Make sure IP forwarding is on if the default gateways are on different
subnets or if the switch is connected to different subnets and those subnets need
to communicate through the switch (which they almost always do).
>> # ip routing
Note: To help eliminate the possibility for a Denial of Service (DoS) attack, the
forwarding of directed broadcasts is disabled by default.
4. Configure BGP peer router 1 and 2 with IPv4 addresses.
>> # router bgp
>> (config-router-bgp)# neighbor 1 remote-address 200.200.200.2
>> (config-router-bgp)# neighbor 1 remote-as 100
>> (config-router-bgp)# neighbor 2 remote-address 210.210.210.2
>> (config-router-bgp)# neighbor 2 remote-as 200
This example shows you how to configure the switch to redistribute information from
one routing protocol to another and create an aggregate route entry in the BGP
routing table to minimize the size of the routing table.
As illustrated in Figure
peer router. Configure the G8000 to redistribute the default routes from AS 200 to
AS 135. At the same time, configure for route aggregation to allow you to condense
the number of routes traversing from AS 135 to AS 200.
25, you have two peer routers: an internal and an external