add ubuntu Dockerfile

ubuntu/Dockerfile

@@ -0,0 +1,27 @@
+FROM ubuntu:16:04
+
+# new a directory for sshd to run
+RUN mkdir -p /var/run/sshd
+
+# installing ssh server
+RUN apt-get update
+RUN apt-get install -y openssh-server wget tmux vim zsh
+
+# installing sudo
+# RUN apt-get install -y sudo
+
+# make ssh services use IPv4 to let X11 forwarding work correctly
+RUN echo AddressFamily inet >> /etc/ssh/sshd_config
+
+# defining user account imformation
+ARG username=czh
+ARG userpasswd=czh
+
+# adding user
+RUN useradd -ms /bin/bash $username && (echo $username:$userpasswd | chpasswd)
+
+# adding user to sudo group
+RUN adduser $username sudo
+
+# setting running application
+CMD /usr/sbin/sshd -D