A good way of checking the connection between the SAP Box and the target Service Box is to use the CL_HTTP_CLIENT class. This basically acts like a browser / web explorer from the SAP Box itself.
Using that client you can prove that SAP can at least see the service it's supposed to be communicating with...
Viewing the content of the "return" variable in the HTML viewer can yield interesting results....
lv_url = 'http://blah-blah-blah/EventLog.asmx'.
* Create Client
call method cl_http_client=>create_by_url
exporting
url = lv_url
importing
client = http_client.
* Send
call method http_client->send
exceptions
http_communication_failure = 1
http_invalid_state = 2.
* Receive
call method http_client->receive
exceptions
http_communication_failure = 1
http_invalid_state = 2
http_processing_failed = 3.
if sy-subrc ne 0.
http_client->response->get_status(
importing
code = lv_ret_code
reason = lv_err_string
).
message lv_err_string type 'I'.
endif.
* Now we have the response , parse , display
* do what you like
return = http_client->response->get_cdata( ).
write: return.