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Flexible server monitoring

Specific DNS not triggering failure on incorrect answer

I have created a 'Specific DNS' test to look for an IP match in the answer (as opposed to any valid IP). I entered a different IP to test the failure notification but it's not failing.

Do I need to do something special for this to work or is it a bug?

My settings are (example values used):

Service: Specific DNS
Name to lookup: example.domain.com
Name server address: ns1.domain.com
IP checking: Result must match: 123.123.123.123
Disable recursive queries: on (ticked)

Notifiers:
Failure - Annoying buzzer

David Sinclair's picture

Re: Specific DNS not triggering failure on incorrect answer

I'd expect it to fail if a different IP were entered... so it sounds like it might be a bug. I'll ask Daniel, the developer of that plug-in, to investigate.

Re: Specific DNS not triggering failure on incorrect answer

Interesting. I have a few more questions to help me understand the problem a little better.

1) Does the Simon monitor window show the test as a failure, and does it show up in the failure log at the bottom of the window? Does it recover as expected when the checked against the correct IP.

2) If it's possible to specify the DNS server address by IP instead of address, does everything work correctly?

3) In the Notification setup (in this case the setup for Annoying Buzzer) I presume you have "Failure" checked. What about "Only notify once for each failure"? If that is un-checked does the notification happen as it should?

Daniel Ellis

May have found cause of problem

It does not show as a failure in monitor window or the log section. The failure log is completely empty.

Changing the name server to an IP address instead doesn't make any difference.

Yes, 'Failure' is ticked in the notifier setup.

OK, I think I found it. I had only changed to the last octet to be wrong. If I change the IP address to be completely wrong (in all octets) then the failure is triggered. I changed it back one octet at a time and it failed if any of the first 3 octets were wrong, but doesn't fail if only the forth is wrong.

RE: May have found cause of problem

I'll check it out!

Thanks,
Daniel

RE: May have found cause of problem

I hate to say it, but I have not been able to repoduce your failure. If you're up for it, I could send you a version of the service that would provide a little more debugging info to help determine the problem.

If you're up for it, all I need is an email address to send the plugin and installation instructions to. Installation is very quick, easy, and can be backed out easily once the debuggin is no longer needed.

Daniel Ellis

What's the best way to give

What's the best way to give you my email address; I don't want to put it here where it might get scraped by bots. And yes I'm happy to try a different version to help with diagnosing this issue.

Charlie Garrison

David Sinclair's picture

Re: What's the best way to give

You can use the Contact form and I'll pass it on to Daniel. Or contact him directly (note, this will only work if you create an account first).