It depends on what the OP intended by "run a C#-generated webservice on
Apache" .
If you want to host logic as a webservice within an apache-based webplex,
then there are a number of options:
1. use the Apache module mentioned previously. [1]. I believe the Apache
module is part of the mono project but IIANM, it is not a requirement that
the ASP.NET runtime be Mono's. In other words you could use the Apache
module (mod_mono) to launch a MS .NET-based webservice, or a mono-based
webservice. However, hosting Microsoft's ASP.NET from mod_mono is probably
not a scenario that MS Premiere support will help you with. Also Mono is
still a work-in-progress project - not completed or completely stable yet,
as far as I know.
2. If you want a simpler, more mainstream approach, you can Reverseproxy
from Apache HTTPD to IIS5/6, which hosts the ASP.NET (ASMX C#) logic. The
existing Apache-based web farm remains. You add a new IIS box, or possibly
just turn on IIS on one of the existing boxes. Of course this box can be
(should be?) different from the front-end HTTP, and can be (should be?)
separated from that front end by a firewall layer, using IPSec or
what-have-you. This is a fully supported scenario.
3. There used to be a commercial product from Covalent that did this. I
haven't seen it very much. I think the company end-of-life'd it. [2] It is
like Mono's Apache module, but I think the Covalent thing required the
covalent Apache 2.0 server - in other words you cannot use just any Apache.
If on the other hand you did not intend to run the webservice on top of an
Apache HTTP, but instead you want to ACCESS the C#-based webservice from an
Apache-based runtime - NB: Apache produces a couple of distinct webservices
runtimes for Java, one is Apache SOAP [3] and the other Apache AXIS [4] -
then that is fairly straightforward. Here we are talking about interop
between Apache SOAP or AXIS and .NET, rather than hosting ASP.NET on Apache
HTTPD.
[1]
http://www.go-mono.com/asp-net.html
[2]
http://www.covalent.net/support/support_announcement.html
[3]
http://ws.apache.org/soap/index.html
[4]
http://ws.apache.org/axis/