Not Found 404 (https://gems.ruby-china.org/specs.4.8.gz
上图的域名已失效
改为
https://gems.ruby-china.com
删除原gem源
gem sources --remove http://gems.ruby-china.org/
添加国内源
gem sources -a https://gems.ruby-china.com
打印是否替换成功
gem sources -l
更换成功后打印如下
https://gems.ruby-china.com
只能存在一个 不然还是会报错