I want to create custom Update Center for internal org plugins.

I try to do it with [juseppe](https://hub.docker.com/r/lanwen/juseppe/).

From my Jenkins server I succeed to download the JSON page via `curl` command.

But when I change the default update site to the new URL I still see the official Jenkins plugins and not my.

I didn't see any log of Update Center when I press the `Check now` button.

Also I try to use the [UpdateSites Manager plugin](https://wiki.jenkins-ci.org/display/JENKINS/UpdateSites+Manager+plugin), but the same problem.

Please advise how I need to configure and where I can find the log of update site.