Redirection not followed by check_http

I assume that should be the same function, so probably not the reason for the different behaviour.

What might explain the difference is calling with the host IP address vs. the host name so the request probably ends up in a different vhost on the server.

BTW, when I try https://updates.jenkins.io/updates/hudson.tasks.Maven.MavenInstaller.json, I do not receive any redirect. Instead the server directly responds with 200 OK and some 6.3K of application/json.