RegEx Validation for DNS SOA seems inverted?

I’ve been experimenting with Synthetic Monitoring (awesome feature!), and set up 12 DNS checks with RegEx Validation for SOA (e g

I’ve set them all to match the RNAME “” for “Validate Answer matches”. All of them fail, expect the one that DOESN’T contain “” (i e

% host -t soa has SOA record 2019100300 28800 7200 4233600 86400
% host -t soa has SOA record 1 7200 900 1209600 86400

I had expected to be the only one that fails, since the SOA doesn’t match my expression.

I figure I might have misunderstood the format, so that I, for example, have to add “.*” in the beginning and end to match the entire string. But in that case I would have expected ALL checks to fail. I fail to understand why is the only one to validate.

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And, no I haven’t checked the “Invert Match” box. If I do the check turns green.

Hey @maggu! It looks like this was a recently resolved bug:

If you are still seeing this issue, please open a Support ticket so our team can further review!

Thanks! Didn’t know Synthetic Monitoring has a GitHub repository.

As I thought then, but good to know for sure what’s going on.

Not the solution I would have preferred perhaps (since double negations aren’t very user friendly, and in most cases you probably want the regex to match), but I can certainly see why it was chosen.