I took your script and ran it on my network. Obviously changing the host, SID, etc. Tcpdump confirmed that it connected to my oracle server.
From: Xymon [mailto:xymon-bounces at xymon.com] On Behalf Of Jeremy Laidman
Sent: Wednesday, September 16, 2015 2:38 AM
To: user-72b9c6c2ac3c@xymon.invalid
Cc: xymon at xymon.com
Subject: Re: [Xymon] Oracle monitoring with dbcheck fails
On 15 September 2015 at 16:59, <user-72b9c6c2ac3c@xymon.invalid<mailto:user-72b9c6c2ac3c@xymon.invalid>> wrote:
This is weird, and it got even more weird when I realized that dbcheck does not even try to communicate with the Oracle instances, it simply logs the error message and exits. I ran tcpdump to verify this and there is no connection attempt being made by dbcheck.
Try running the script through strace.
This communication is the property of CenturyLink and may contain confidential or privileged information. Unauthorized use of this communication is strictly prohibited and may be unlawful. If you have received this communication in error, please immediately notify the sender by reply e-mail and destroy all copies of the communication and any attachments.