Log stash plugin update failed with connection error

I have setup proxy and I can do curl/wget properly with the proxy. I have got both http and https proxy setup. I have also exported them to both lowercase and uppercase, e.g. https_proxy and HTTPS_PROXY.

But still trying to update plugin fails:

$ bin/plugin update logstash-input-beats
ERROR: Updated Aborted, message: Connection refused - Connection refused

Install works file.

Is there a way to manually download the updates locally and install it?

According to https://www.elastic.co/guide/en/logstash/current/working-with-plugins.html#proxy-plugins you should set HTTP_PROXY, not HTTPS_PROXY. That page also describes how to install a downloaded gem by hand.

Have tried that, no luck. I have all 4 combinations setup, http_proxy, https_proxy, HTTP_PROXY, HTTPS_PROXY.

I've got the exact same issue, update won't work for us at all but install works fine. To update our plugins we've chosen to run
for i in $(/opt/logstash/bin/plugin list); do /opt/logstash/bin/plugin install "$i"; done

The update function has given us nothing but trouble since the plugin system was introduced.

This works with proxy,