CSS - load balance backend communication

Unanswered Question
Jan 16th, 2008

Hi guys,

I need LB something like this in routed mode:

first data flow:


and second (backend) flow is:


vip1,2-c = VIP address on client side

www1,2,3,4 = all servers are in the same VLAN

problematic is second data flow (www1/2 -> vip2 -> www3/4(because www3/4 are in the same VLAN as www1/2).

I have two solution for this:

1. migrate www1/2 and www3/4 to the independent VLANs (this can be design problem in existing topology)

2. communication from www1/2 with destination to www3/4 translate to IP address located on the CSS using group, but I'm not sure if it's possible, or how it's possible to configure on the CSS.

group gr1

add service www1

add service www2

add destination service www3

add destination service www4

vip address ip-from-client-side(for example vip2-c)


it's possible to use this configuration?


I have this problem too.
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Gilles Dufour Wed, 01/16/2008 - 05:51

The group is a good solution.

However, the way it was configured is incorrect.

You either specify the source or destination.

So, if you want to nat all traffic from www1 and www2 you leave the 'add server www1' commands and remove the 'add destination service www3'.

Or you can nat all traffic going to www3 and www4. In this case, you remove the 'add service www1' and keep the others.

Another way of doing this would be to remove all 'add ..' commands and use an acl to specify when to use the group using the option 'sourcegroup gr1' inside the acl.



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