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New Member

Load balancer to dual ISP

Hello all,

I have dual cico routers connecting to dual isp.Inside of the both routers ethernet interfaces are being connected to the dual redundant ASA5520 firewall.Now the customer wants to insert some sort of load balancer in beetween the firewall and router pairs.

Instead of directly connecting the firewalls to the out side routers we need to put the load balancer that would connect the both firewall and routers.

Is there any device cisco has in place.

What about CSS11500 this device for server load balanceing only.

What about the GLBP.Please could someone clear me how can i choose the best solution for this scenarios.




Re: Load balancer to dual ISP


There are some enterprise level load balancing solution available from non-cisco companies link RAD

Load balancing can also be achived in your setup without inclusion of any more hardware.

You just need to talk to your ISPs for BGP ASs.Then you can configure the edge routers for that and load-balancing can be achieved.



Re: Load balancer to dual ISP


Let us know what is the objective of putting the load balancer in between firewall and routers.

You can also try the following;

1. BGP between your two routers and your two ISP. Provided you have your own ASN and IP Address

2. GLBP firewall gateway in the two routers

3. Active/Active firewall setup (R/R load balancing)

Doing the above, you may not need to invest for a separate load balancer unless you want to load balance your server (i.e. web server).

New Member

Re: Load balancer to dual ISP

Loadbalancing with BGP requires the entire routing table - if you are going that way make sure your routers can handle that....

another method is, well to be hosnest a little crazy - but it works. ---> gateway ISP 1 ----> geateway ISP 2

keep in mine this works well for outbound traffic only- an is not true load balancing....

Re: Load balancer to dual ISP

FYI, BGP is not load balancing, its load sharing. If you are connected to two ISP, there are many ways to do load balancing for outbound traffic, but for inbound traffic, BGP load sharing is the best option.

New Member

Re: Load balancer to dual ISP


are your ASAs configured in failover mode - active/passive? IN that case you are have only one active firewall. For loadsharing traffic between outside routers (your border routers), you may think of configuring HSRP on both router ethernet interfacee - 2 hsrp groups having each router as active on either of the group at a time.