ACE SM in bridge mode

[axfalk]

We're trying to figure out which mode (bridge or routed) we should configure a pair of ACE SM's on the core and I have a quick question in conjunction with a bridge mode.

In a load-balance request, a packet will arrive at the VIP, and the ACE will pick the appropriate server and then use the destination Network Address Translation (NAT) to send the client request to the server. The server will respond using the interface VLAN of the MSFC as its default gateway to the client. At this juncture, the ACE will change the source IP back to the VIP and bridge the traffic to the MSFC. How would the flow be different if a request were not for load-balancing, but just for a specific server. Would the ACE still do the destination NAT and then change the source back to the VIP on the returned packet? - how does ACE differentiate between a load balanced vs a non load balance request, since they both come in on the same VIP vlan?

Thanks..

[Peter Koltl]

Traffic to specific rservers is just routed/bridged (though a 2-leg connection is maintained in ACE connection table). No NAT. Traffic to VIP is implicitly NAT'ed as you write. This type of traffic is recognized by L3/L4 class-maps (match virtual-address). Decision is based on destination IP address and port.