EIGRP load balancing

Morning all,

I have a small issue that I can't work out why I have it.

I use EIGRP at work, and have two routes from one building to another. One way across is our wireless bridge, and the other is a fibre.

I have configured vlan interfaces for these links, and these vlan interfaces are the ones used for EIGRP. The bandwidth of the wireless is set to 54000, and the fibre is set to 100000.

My query is this, the routing table shows routes using both of these links, both with the same FD/RD. Can anyone explain what's going on here?

One building has clustered 6509s, and these link across to a 3550.

Regards

James

Reply to
James
Loading thread data ...

Without seeing your configs, I doubt anyone here can help you you. At a minimum you need to post the interface and eigrp configs from all four routers.

Reply to
Thrill5

OK, here are the parts I think are important to this query - many thnaks for anyone that can help me with this.

Core 1 - 6509 - cluster with core 2

interface Vlan407 description *** Second Floor Users *** bandwidth 54000 ip address 10.150.42.252 255.255.255.0 ip helper-address 10.x.x.x ip helper-address 10.x.x.x ip pim sparse-dense-mode standby 1 ip 10.150.42.254 standby 1 timers 1 3 standby 1 priority 200 standby 1 preempt

interface Vlan550 description *** Fibre Link to old building *** bandwidth 1000000 ip address 192.168.206.1 255.255.255.248 standby 1 ip 192.168.206.3 standby 1 priority 200 standby 1 preempt ! router eigrp 1 passive-interface default no passive-interface Vlan407 no passive-interface Vlan550 network 10.150.42.0 0.0.0.255 network 192.168.206.0 0.0.0.7 no auto-summary

Core 2 - 6509 - cluster with core 1

interface Vlan407 description *** Second Floor Users *** bandwidth 54000 ip address 10.150.42.253 255.255.255.0 ip helper-address 10.x.x.x ip helper-address 10.x.x.x ip pim sparse-dense-mode standby 1 ip 10.150.42.254 standby 1 timers 1 3 standby 1 preempt

interface Vlan550 description *** Fibre Link to old building *** bandwidth 1000000 ip address 192.168.206.2 255.255.255.248 standby 1 ip 192.168.206.3 standby 1 preempt ! router eigrp 1 passive-interface default no passive-interface Vlan407 no passive-interface Vlan550 network 10.150.42.0 0.0.0.255 network 192.168.206.0 0.0.0.7 no auto-summary

Cisco 3550

interface Vlan407 bandwidth 54000 ip address 10.150.42.3 255.255.255.0 ! interface Vlan550 description Test IP for Fibre_Link bandwidth 1000000 ip address 192.168.206.5 255.255.255.248 ! router eigrp 1 redistribute static network 10.1.28.17 0.0.0.0 network 10.1.128.34 0.0.0.0 network 10.52.1.0 0.0.0.3 network 10.150.33.0 0.0.0.127 network 10.150.42.0 0.0.0.255 network 10.0.0.0 network 192.168.70.0 network 192.168.200.0 network 192.168.203.0 0.0.0.3 network 192.168.205.0 network 192.168.206.0 0.0.0.7 network 194.227.32.0 no auto-summary eigrp log-neighbor-changes

Snippet from the routing table of one of the 6509s

D 194.189.73.64 [90/1820416] via 192.168.206.5, 6d08h, Vlan550 [90/1820416] via 10.150.42.3, 6d08h, Vlan407

The above is what I'm a little confused about. It appears to me that they are being load-shared. When I do a traceroute though, the fibre link always seems to be the one used, which is correct.

Thrill5 wrote:

Reply to
James

Take off the bandwidth statements on the 3550, they are not required and do not do what you intend.

Without your topology, I can't say for sure but I'm assuming that these VLANs exist in both buildings, and thus you are not routing any traffic between buildings, you are switching traffic. That is why the bandwidth is the same for both routes because they are directly attached at both ends.

Scott

Reply to
Thrill5

Your assumptions sound pretty good to me, I'll try what you said and let you know how it goes.

Many thanks for your reply.

James

Thrill5 wrote:

Reply to
James

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.