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Community Member

VIP on the same subnet as real addresses?

We purchased a css11501 to load balance traffic between a handful of servers that run a telnet-based application. As I understand it, the VIP is usually on a seperate IP subnet than the server real addresses. Are there any disadvantages of keeping the VIP and server real addys on the same subnet (if this can even be done)? If we do this, than any non-loadbalanced traffic would avoid the css.

Thanks for any help you can provide!

Steve Wegrzyn


Re: VIP on the same subnet as real addresses?

The issues with having the VIP and servers on the same subnet are the same as running in "one-arm" mode, since that's effectively the config that you need to use.

Main issues are having to NAT the incoming connections source addresses, and performance constraints around having traffic ingress and egress the same port on the CSS. (But I've got to think that the 11501 was brought to market with this design in mind with the single gigabit port.)

As long as your servers don't need visibility to the actuall IP addresses for incoming connections, this should work fine. Just remember to setup your NAT groups.

Community Member

Re: VIP on the same subnet as real addresses?

Thanks for the quick response, that answered my question.

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