In a corporate network environment, a proxy server is often used. If you set up a proxy server in ubuntu’s some application, you’ll get a good network connection only that application,
So Any other http or https connection other application is still impossible.
Then, the following system wide proxy configuration is needed.
#export http_proxy=http://proxy_host:port #export https_proxy=http://proxy_host:port
If that proxy need to login, you can use to command line below
#export http_proxy=http://user:pass@proxy_host:port #export https_proxy=http://user:pass@proxy_host:port
If you want to keep your configuration system-wide, you can enter it in /etc/environment or /etc/profile.
It’s also some use Centos.