ACE probing of "virtual hosts" on web servers

bruno.quesnel · ‎05-04-2010

We got some web servers that hosts multiple web sites and would like to probe each of these sites. Is there a way to configure a probe to present the request for a particular web site versus the other without falling into the catch all clause of the http server configured on the box ?

Thanks

ciscocsoc · ‎05-05-2010

Hi,

Have you tried using a scripted probe?

probe scripted USE_HTTP_SCRIPT

script HTTP_PROBE_SCRIPT "GET http//:www.wibble.com/index.html HTTP/1.0" html 0

Normally with a GET you don't use the absolute URI, but the W3C standard do allow it and all HTTP/1.1 must handle it. You would need one probe

instance per Virtual Server. Alternatively use the provided sample probe and modify it to take additional arguments.

HTH

Cathy

bruno.quesnel · ‎05-05-2010

thanks for the answer, but this one sparks 2 more questions :

- Where can I find the official documentation for the scripts

- Does the script natively support authentication or do I need to modify the script ? I would have a need for some of the sites to pass credentials for proper tests.

Thanks

ciscocsoc · ‎05-05-2010

The scripts are documented in the Server Load Balancing Manual.

My understanding is that the scripts provided by Cisco are samples and they are not supported - and AFAIK you can't raise TAC cases against them. If you need authentication then you'll have to work out how to do that using the Tcl methods available - but if you go beyond "basic" authentication it will get very messy very quickly.

It might be easier to have another system (e.g. Nagios) do the probing and setting the contents of a status page on the main server appropriately. Then use can use the HTTPCONTENT probe.

HTH

Cathy

Sean Merrow · ‎05-05-2010

Hello Folks,

I wonder if you could get away with just using the built-in HTTP probe rather than the scripted probe? With the built-in HTTP probe, you can configure all sorts of HTTP headers, including the Host header which might be all you need for your server hosting multiple sites.

Just to clarify on the support for scripted probes that TAC supports: If the script is downloaded from cisco.com, and is not modified, then TAC will support it. It is not supported if it is modified, and TAC will not support custom-created scripts.

Hope this helps,

Sean