Ubuntu 16.04在搭建Redis Cluster搭建时，使用gem install redis时出现：ERROR: While executing gem ... (Gem::FilePermissionError) You don't have write permissions for the /var/lib/gems/2.3.0 directory.
注意：千万不要使用sudo来执行gem install redis。
解决方法：
sudo apt-get update
sudo apt-get install git-core curl zlib1g-dev build-essential libssl-dev libreadline-dev libyaml-dev libsqlite3-dev sqlite3 libxml2-dev libxslt1-dev libcurl4-openssl-dev python-software-properties libffi-dev
cd
git clone https://github.com/rbenv/rbenv.git ~/.rbenv
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
echo 'eval "$(rbenv init -)"' >> ~/.bashrc
exec $SHELL
git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build
echo 'export PATH="$HOME/.rbenv/plugins/ruby-build/bin:$PATH"' >> ~/.bashrc
exec $SHELL
rbenv install 2.3.1
rbenv global 2.3.1
ruby -v
最后安装
gem install redis
rbenv rehash
如果不想使用上面的方法，可以使用以下的投机取巧的方法，给上面错误的文件夹增加权限
sudo chmod 777 /var/lib/gems/2.3.0/
sudo chown -R administrator /var/lib/gems
说明：administrator为当前登录的用户，根据实际情况更改。
然后再次执行：
gem install redis
参考：
