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