EIGRP Bandwidth for IPv4
EIGRP utilizes 50 % of an interface’s bandwidth for EIGRP information by default. Utilizing a half interface bandwidth not allowing enough bandwidth for the routing of normal traffic and prevents the EIGRP process from over-utilizing a link.
We can change to default bandwidth utilization ratio using the command “ip bandwidth-percent eigrp”. This is an interface mode command which changes the percentage of bandwidth that can be used by EIGRP on an interface. The command syntax for changing the interface bandwidth is:
Router(config-if)# ip bandwidth-percent eigrp as-number percent
This command is useful, where the link speed is slow. If the link speed is slow then we can configure the bandwidth utilization for EIGRP. Figure 1 illustrates the link between R1 and R2 share a slow 128 kb/s link. So we required to configure the bandwidth usage limitation for EIGRP. The configuration for bandwidth limitation for EIGRP between the R1 and R2 is the following:
R1(config)# interface gigabitEthernet 0/0
R1(config-if)#ip bandwidth-percent eigrp 100 25
R2(config)# interface gigabitEthernet 0/0
R2(config-if)#ip bandwidth-percent eigrp 100 25
In the above example, EIGRP is limited to use up to 25 percent of the link’s bandwidth. So, EIGRP never uses more the 32 kb/s of the link’s bandwidth for EIGRP packet traffic. We can restore the default value, using the no form of the “ip bandwidth-percent” command.
EIGRP Bandwidth for IPv6
We can also configure the EIGRP for IPv6 bandwidth limitation also. The “ipv6 bandwidth-percent eigrp as-number percent” command can be used to configure the limitation for IPv6 EIGRP. The command should be used similarly in the interface configuration mode. We can restore the default value, using the no form of this command.