HAProxy - forward to a different web server based on URI

Solution 1:

Here is a blog post I wrote on load balancing based on the host headers:

http://www.mattbeckman.com/2009/09/18/using-the-acl-in-haproxy-for-load-balancing-named-virtual-hosts/

If you would like to match against a URI or directory, I would suggest using path_beg instead of hdr_end that is used in the example provided on that page. Below is an example of how you might do this with your configuration:

frontend http-in
    bind 10.254.23.225:80
    acl has_special_uri path_beg /special
    use_backend special_server if has_special_uri
    default_backend webfarm

backend webfarm
    balance roundrobin
    cookie SERVERID insert
    option httpchk HEAD /check.txt HTTP/1.0
    option httpclose
    option forwardfor
    server webA 10.254.23.4:80 cookie webA check
    server webB 10.248.23.128:80 cookie webB check

backend special_server
    balance roundrobin
    cookie SERVERID insert
    option httpchk HEAD /check.txt HTTP/1.0
    option httpclose
    option forwardfor
    server webC 10.0.0.1:80 cookie webC check

Hope that helps!