Headless serverFrom your expanded zeppelin directory:
cp conf/zeppelin-site.xml.template conf/zeppelin-site.xml
And change zeppelin.server.addr to be either the IP address or the domain name of this server. This is to allow outside connections.
ProxyZeppelin seems to need npm from node.js, which in turn needs to know your proxy settings. To get around this, install node.js yourself (instead of relying on what is built in to Zeppelin) and execute npm config to set its proxy settings. Below includes the instructions for installing node.js onto RedHat-type Linux distributions (CentOS, Oracle Linux, etc.). See nodejs.org for other OS's.
export http_proxy=<your http proxy>
export https_proxy=<your https proxy>
wget curl --silent --location https://rpm.nodesource.com/setup_6.x
chmod 777 setup_6.x
sudo yum install -y nodejs
npm config set proxy <your http proxy>
npm config set https-proxy <your https proxy>