Load Balancing

[rickyjohnth]

There are two Unix server A and B acting as a reverse proxy server.

Both the server A and B Natted with public IP to C and D respectively on Cisco ASA 5540 firewall.

The Public IP C and D got registered in public DNS server for Domain name registration using round robin method.

Now the requirement is if the server A goes down will the firewall Cisco ASA automatically redirect the whole traffic towards B server? This is something load balance support providing on Cisco ASA firewall.

[mirober2]

Hi Ricky,

Unfortunately, the ASA does not support this functionality. The static NAT statements that you have configured that map A to C and B to D are not aware of the status of the servers, so if a client tries to connect to C, the ASA will try to forward the request on to A regardless of the status of A.

This type of functionality is usually acheieved with a dedicated load balancer, which will keep track of the state of your servers and route the requests accordingly.

Hope that helps.

-Mike