Apache and IIS side by side (both listening to port 80) on windows2003

What are some good ways to do this? Is it even possible to do cleanly?

Ideally I'd like to use packet headers to decide which server should handle requests. However, if there is an easier/better way let me know.

Solution 1:

It's impossible for both servers to listen on the same port at the same IP address: since a single socket can only be opened by a single process, only the first server configured for a certain IP/port combination will successfully bind, and the second one will fail.

You will thus need a workaround to achieve what you want. Easiest is probably to run Apache on your primary IP/port combination, and have it route requests for IIS (which should be configured for a different IP and/or port) to it using mod_rewrite.

Keep in mind that the alternative IP and port IIS runs on should be reachable to the clients connecting to your server: if you only have a single IP address available, you should take care to pick an IIS port that isn't generally blocked by firewalls (8080 might be a good option, or 443, even though you're running regular HTTP and not SSL)

P.S. Also, please note that you do need to modify the IIS default configuration using httpcfg before it will allow other servers to run on port 80 on any IP address on the same server: see Micky McQuade's answer for the procedure to do that...

Solution 2:

I found this post which suggested to have two separate IP addresses so that both could listen on port 80.

There was a caveat that you had to make a change in IIS because of socket pooling. Here are the instructions based on the link above:

1. Extract the httpcfg.exe utility from the support tools area on the Win2003 CD.
2. Stop all IIS services: net stop http /y
3. Have IIS listen only on the IP address I'd designated for IIS: httpcfg set iplisten -i 192.168.1.253
4. Make sure: httpcfg query iplisten (The IPs listed are the only IP addresses that IIS will be listening on and no other.)
5. Restart IIS Services: net start w3svc
6. Start the Apache service