I try Logstash update 6.5.4 → 6.6.0.(Via proxy)
The following error message will fail and fail.
Error Bundler::HTTPError, retrying 1/10 Could not fetch specs from https://rubygems.org/
But It will succeed if it does not go through the proxy.
Check the following and both 「HTTPS_PROXY=http://」and 「HTTP_PROXY=http://」 settings are done.
Also, Elasticsearch has successfully updated plugins via a similar proxy.
Is there any procedure or mistake?