Hello! I’m trying to set up an HTTP check synthetic transaction (Grafana) to check the health (up/down) of my Jenkins server, but I always get a HTTP 401 back, when I expect a HTTP 200 since I’m connecting to an unauthenticated endpoint ( https://my-jenkins-host/ ). When I try the same URL with cURL …

hmm, when I do not grant Overall/Read to anonymous then I get a 403 from Jenkins, when granted I get 200 with curl. I get a 401 only when I use wrong password or a non existing user. Is grafana maybe under the hood adding some user/pwd? Maybe check the access logs of Jenkins (if you have enabled t…

Thanks for your reply @mawinter69 ! One of the first things I did indeed enable was the Jenkins access log, but I didn’t see anything useful in it. I compared a request from my browser (where I get 200) and a request from Grafana and the only difference in the log output is http 401. The User-Agent…

@mawinter69 - I found Grafana is adding an Authorization header ("Authorization":"Basic Og==") that contains the character “:” (colon) when I don’t set a Basic Auth header. I think that’s throwing off Jenkins which will try to process it and find it invalid, hence the 401. I will ask their support a…

Getting HTTP 401 (Unauthorized) with Jenkins http check (synthetic)

Using Jenkins

cotjoey (Joey Cote) April 17, 2024, 1:36pm 5

Grafana removed the Basic Auth header that they were adding automatically (even if I don’t set it manually). That fixed the issue.

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Getting HTTP 401 (Unauthorized) with Jenkins http check (synthetic)

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