One of the configured repositories failed (Centos 2.1903 - x86_64 - Erlang Solutions),
and yum doesn't have enough cached data to continue.
解决方法
使用sudo yum install erlang安装erlang时报错，最后改成这个就成功了：
sudo yum install erlang --disablerepo=erlang-solutions
或者
sudo yum install erlang --disablerepo=erlang-solutions ...
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