oh-my-zsh安装

install zsh first

yum install -y zsh

clone and install oh-my-zsh

sh -c "$(curl -fsSL https://raw.github.com/robbyrussell/oh-my-zsh/master/tools/install.sh)"

or

sh -c "$(wget https://raw.github.com/robbyrussell/oh-my-zsh/master/tools/install.sh -O -)"

modify theme to agnoster

sed -i 's/robbyrussell/agnoster/g' ~/.zshrc
or
sed -i 's/robbyrussell/ys/g' ~/.zshrc
source ~/.zshrc

change default shell to zsh

echo $ZSH_VERSION 
sudo chsh -s $(which zsh)