列出某个软件的所有版本号：
yum module list nginx
red hat enterprise linux 8 for x86_64 - appstream (rpms)
name stream profiles summary
nginx 1.14 [d] common [d] nginx webserver
nginx 1.16 common [d] nginx webserver
nginx 1.18 common [d] nginx webserver
nginx 1.20 [e] common [d] nginx webserver
hint: [d]efault, [e]nabled, [x]disabled, [i]nstalled
设定某个版本为默认版本
yum module enable nginx:1.20
安装默认版本
yum install nginx