[Xymon] http test

[Martin Flemming]

On Thu, 18 Jul 2013, Henrik Størner wrote:

> On 14-07-2013 15:15, Martin Flemming wrote:
>> Can somebody tell me  how the http-check work ?
>> 
>> .. i see nothing like "curl, etc." in the source
>> 
>> xymonnet/httptest.c
>
> Xymon does all of the HTTP request generation and network stuff by itself.
>
>
>> The reason ist, that after a normal http-check on a windows-server,
>> the application craches .. .i can't believe that the xymon-http-test
>> should be the reason, but i've to tell how does xymon test a webside ...
>
> Unfortunately, there is no debugging option in xymonnet so it shows exactly 
> what is being sent to the server. And it depends on the exact test you have 
> in hosts.cfg.
>
> Assuming this is a simple URL test (no POST data or other special stuff), 
> then a test like
>
> 	10.0.0.1  mywebserver	# http://web.example.com/myapp/
>
> would trigger this request:
>
> 	GET /myapp/ HTTP/1.1
> 	Connection: close
> 	Host: web.example.com
> 	User-Agent: Xymon xymonnet/4.3.11
> 	Accept: */*
> 	Pragma: no-cache
>
> My guess would be that it crashes on the "User-Agent" string because it 
> doesn't handle unknown useragents (browsers) correctly. I've seen that 
> happen.
>
>
> A network sniffer on the Xymon server can tell you exactly what is being sent 
> and received - e.g. wireshark. You can also use tcpdump or snoop and still 
> analyse the data with wireshark - that is much easier than reading the raw 
> output from tcpdump.
>

Thanks a lot for explanation, henrik !

cheers,
 	martin