gem install redis命令执行时出现了：

ERROR:  Error installing redis:

    redis requires Ruby version >= 2.3.0.  解决办法：

1.安装curl：yum install curl

2. 运行 ：curl -sSL https://rvm.io/mpapis.asc | gpg2 --import -

3.运行：curl -sSL https://rvm.io/pkuczynski.asc | gpg2 --import -

4.curl -L https://get.rvm.io | bash -s stable

5.find / -name rvm.sh

6.source /etc/profile.d/rvm.sh

7.rvm requirements

8.rvmsudo yum install -y gcc-c++ patch readline readline-devel zlib zlib-devel libyaml-devel libffi-devel openssl-devel make bzip2 autoconf automake libtool bison iconv-devel

9.source /usr/local/rvm/scripts/rvm

10.rvm list known

11.rvm install 2.3.8

12.rvm use 2.3.3

13.rvm remove 2.0.0

14.ruby --version

15.gem install redis

配置教程参考：https://www.cnblogs.com/Camiluo/p/10996934.html