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Benoit_C_'s avatar
Benoit_C_
Oct 06, 2015

HTTP monitor receive string : how to not take the '200 OK' into account

Hello, I have to monitor a page which give in its body 'OK' if server is OK and KO if the server is down. As a 'receive string', I use 'OK'. The problem is that 'OK' is already present in the 'HT...
application delivery
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Benoit_C_'s avatar
Benoit_C_
Oct 06, 2015

Hi Brad,

 

thanks for the answer.

 

Yes that's what I put in place: KO as a receive string.

 

But I think i'm confused because of this SOL: https://support.f5.com/kb/en-us/solutions/public/12000/800/sol12818.html (the table with results of matching)

 

Because then I could end in a situation where both 'receive string' and 'receive disable string' will match: OK because of the 'HTTP/1.1 200 OK' KO because of the body of the page

 

I'll continue to dig this and take dumps. But so far I observe a lot of flaps on servers for which I apply this monitor, and am wondering if it could be related to the strings I trying to match.

 

(For info I more or less follow the best practice 'Timeout = 3x Interval + 1')

 

Br,

 

Ben

 

Valentine_96813's avatar
Valentine_96813
Icon for Nimbostratus rankNimbostratus
Apr 21, 2016
Health monitors are first exact match. If there are more than one, it takes the first. I have seen issues with monitors because of this. Also, keep in mind that health monitors don't look at the entire page. https://support.f5.com/kb/en-us/solutions/public/3000/400/sol3451.html