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http sensor, ignore "HTTP/1.1 401 Unauthorized"



I need to check http server where authentication is required. I don't want to log in, just check that there is web server response on that port and address, 401 is good enoug. Is there some way for me to ignore the 401, and return OK to the PRTG as long as I'm getting response from the web server.

Thanks Petr

401 http unauthorized

Created on Jan 11, 2011 5:08:33 PM

3 Replies



Seeing as 401 is an error message the sensor would always turn red. The only option would be to provide the necessary credentials to log in, otherwise the sensor will fail.

However, would monitoring the port in case suffice? If so, you could use a port sensor instead.

Created on Jan 13, 2011 4:14:11 PM by  Patrick Hutter [Paessler Support] (7,225) 3 3



What if we need to monitor external services behind of ip address (for example IP1:PORT/service1, IP1:PORT/service2), and no need to put credentials because those are external services used by some applications (and external service didn't give another creds to use monitoring), 401 is ok in this case, it means that service is up and just 5xx makes sense. Port sensor is worthless in this case, because port usually opened on Firewall and services are terminated on FW. Here https://kb.paessler.com/en/topic/65731-which-http-status-code-leads-to-which-http-sensor-status#reply-214810 you say that "You need to manually configure your HTTP sensors only if you want to change these default reactions." - where can we configure it "manually"?

Created on Nov 28, 2022 10:31:09 AM



You can adjust the sensor status based on limits and/or keyword checks, however you cannot change the behavior of the HTTP Sensor for HTTP status codes. If you want the sensor to be in UP/Ok state for HTTP status code 401, you can however use custom sensors. These articles might help:
- https://kb.paessler.com/en/topic/47373
- https://kb.paessler.com/en/topic/65232

Created on Dec 1, 2022 11:37:33 AM by  Timo Dambach [Paessler Support]

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