apt-get proxy:
sudo gedit /etc/apt/apt.conf
Acquire::http::Proxy "http://10.11.70.71:80";
common proxy:
sudo gedit ~/.bashrc
export http_proxy=http://10.11.70.71:80/
c1
ssh-keygen -f ~/.ssh/c1
ssh-copy-id -i .ssh/c1.pub han@10.11.58.85
sudo gedit .ssh/config
host mars
user han
hostname 10.11.58.85
port 22
identityfile ~/.ssh/c1
ssh mars