Two servers on same machine, with apache proxing requests for the other one

Hope someone can help. I'm running apache v2.2.2 on Windows port 80. I
also run another application that requires HTTP access on the same
machine, port 81. Unfortunately, some machines I use off-site only allow
port 80 outgoing access.

How do I tell apache to reverse-proxy requests to the other application?

Eg.

http://www.abc.com/* should be handled by apache except for
http://www.abc.com/app should be forwarded to http://www.abc.com:81
--
David Mahon

In article <slrneas0uh.1ob.davideyeahsure@fogg.onlyforfun.net >, Davide
Bianchi <davideyeahsure@onlyforfun.net> writes
>On 2006-07-06, David Mahon <news@amigo.co.uk> wrote:
>> How do I tell apache to reverse-proxy requests to the other application?
>
>ProxyPass /app http://...:81/
>ProxyPassReverse /app http://...:81/
>
>The problem in this case is that, if the 'target' application is using
>/index.html in an URL, that won't be translated into /app/index.html
>so you'll get the wrong page or a 404.
>
>The best would be to use a VHost and redirect everything from the root
>of the VHost instead of just /app.

How do I do it? I have a spare domain name (lets call it xxxxxxxx.com)
so I can just forward the entire domain to the other application.

I've tried using the following in the httpd-vhosts.conf

<VirtualHost *:80>
ProxyPreserveHost On
ProxyPass / http://127.0.0.1:81
ProxyPassReverse / http://127.0.0.1/:81
ServerName www.xxxxxxxx.com
</VirtualHost>

but then I can't start apache (it fails, nothing in the log file but
service specific error 1 in Windows Event Viewer). As soon as any of the
lines begging "Proxy" are present, Apache fails to start.
--
David Mahon

In article <0c35rTBnUrrEFwEE@earth.amigo.co.uk>, David Mahon
<news@amigo.co.uk> writes

>I've tried using the following in the httpd-vhosts.conf
>
><VirtualHost *:80>
>ProxyPreserveHost On
>ProxyPass / http://127.0.0.1:81
>ProxyPassReverse / http://127.0.0.1/:81
>ServerName www.xxxxxxxx.com
></VirtualHost>
>
>but then I can't start apache (it fails, nothing in the log file but
>service specific error 1 in Windows Event Viewer). As soon as any of
>the lines begging "Proxy" are present, Apache fails to start.


Sorry, please ignore.

The proxy modules were not loaded in the default apache configuration.
Now I've turned them on and got it working.
--
David Mahon