OSPF load balance in HSRP

[acbenny]

Hi expert,

I am setting a lab to test the load balance. Noramlly, 2620 will be act as active HSRP router and 3620

will be the standby HSRP. the HSRP is work well and I want to add

OSPF load balancing in this HSRP module whatever in 2620 active router or 3620 standby router once it become active.

Is it possible ? I know there is MHSRP that can load sharing the

traffic by dividing 10.1.1.0/24 into two HSRP group. However,

I don't want to use it. If OSPF load balance can 't be worked in this diagram,

does EIGRP can be worked which support unequal cost ?

Thanks for your help

[acbenny]

Attach the Router configure

[sundar.palaniappan]

I think GLBP, Gateway Load Balancing Protocol, is probably what you need. This would provide load sharing over multiple routers using a single virtual IP address while providing failover support at the same time. This combined with routing protocol metrics, which can be tweaked, should help you accomplish what you intend to do.

See the link for more info on GLBP:

http://www.cisco.com/en/US/products/ps6550/products_white_paper09186a00801541c8.shtml#wp1027258

HTH

Sundar

[acbenny]

Thank you for Sundar 's help, but i am sorry that my router can't support GLBP this command. So does OSPF or EIGRP(unequal metric load balance) can acheive it?

[Richard Burts]

Jack

OSPF will provide good support for the redundancy shown in your diagram. But if you want load sharing (some of the traffic from 10.1.1.0 sent via the path through 172.20.1.0 and some traffic sent via the path through 172.20.1.4) and you want it to work on both the 2620 and the 3620, I do not see any way that either OSPF or EIGRP could do that.

If you really want load sharing in that environment I would suggest that you investigate Policy Based Routing as a way to accomplish this.

HTH

Rick

[acbenny]

So, base on the above network connection, I remove the HSRP in 2620 and 3620 and configure those five router to run as EIGRP.

Can I achieve the network (192.168.169.0/24) by unequal load balance now ? How Can I do it ?

2620#sh ip route

172.20.0.0/30 is subnetted, 2 subnets

C 172.20.1.0 is directly connected, Serial0/0

D 172.20.1.4 [90/2195456] via 10.1.1.2, 01:01:43, Ethernet0/0

10.0.0.0/24 is subnetted, 1 subnets

C 10.1.1.0 is directly connected, Ethernet0/0

D 192.168.169.0/24 [90/2195456] via 172.20.1.1, 01:01:43, Serial0/0

3620#sh ip route

172.20.0.0/30 is subnetted, 2 subnets

D 172.20.1.0 [90/2195456] via 10.1.1.1, Ethernet1/0

C 172.20.1.4 is directly connected, Serial1/0

10.0.0.0/24 is subnetted, 1 subnets

C 10.1.1.0 is directly connected, Ethernet1/0

D 192.168.169.0/24 [90/2195456] via 172.20.1.5, Serial1/0

[Richard Burts]

Jack

If you set the variance under router EIGRP you may get EIGRP to put both paths into the route table and to do unequal cost load share. We could see better how it would work if you post the output of show ip eigrp topology 192.168.169.0 255.255.255.0.

HTH

Rick

[acbenny]

Hi Rick, the capture result is as below. Could you also explain how it can be done

Thanks for your help !

2620#sh ip eigrp topology 192.168.169.0/24

IP-EIGRP (AS 1): Topology entry for 192.168.169.0/24

State is Passive, Query origin flag is 1, 1 Successor(s), FD is 2195456

Routing Descriptor Blocks:

172.20.1.1 (Serial0/0), from 172.20.1.1, Send flag is 0x0

Composite metric is (2195456/281600), Route is Internal

Vector metric:

Minimum bandwidth is 1544 Kbit

Total delay is 21000 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 1

10.1.1.2 (Ethernet0/0), from 10.1.1.2, Send flag is 0x0

Composite metric is (2221056/2195456), Route is Internal

Vector metric:

Minimum bandwidth is 1544 Kbit

Total delay is 22000 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 2

3620#sh ip eigrp topology 192.168.169.0 255.255.255.0

IP-EIGRP topology entry for 192.168.169.0/24

State is Passive, Query origin flag is 1, 1 Successor(s), FD is 2195456

Routing Descriptor Blocks:

172.20.1.5 (Serial1/0), from 172.20.1.5, Send flag is 0x0

Composite metric is (2195456/281600), Route is Internal

Vector metric:

Minimum bandwidth is 1544 Kbit

Total delay is 21000 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 1

10.1.1.1 (Ethernet1/0), from 10.1.1.1, Send flag is 0x0

Composite metric is (2221056/2195456), Route is Internal

Vector metric:

Minimum bandwidth is 1544 Kbit

Total delay is 22000 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 2

[Richard Burts]

Jack

I believe that for EIGRP unequal cost load balancing to work, the second route must qualify as a feasible successor. The output that you have posted shows that the second route is not a feasible successor. So I believe that you will not get unequal cost load balancing to do what you want. You could set variance of 2 under router eigrp and see what happens. But I believe that it will not work as you desire.

HTH

Rick