我安装zlib出错：
yum install zlib-1.2.3-29.el6.i686
Error: Protected multilib versions: zlib-1.2.3-29.el6.i686 != zlib-1.2.3-27.el6.x86_64
You could try using --skip-broken to work around the problem
You could try running: rpm -Va --nofiles --nodigest
原因：多个库共存冲突
解决办法：在执行命令后面加上：--setopt=protected_multilib=false
再次执行：yum install zlib-1.2.3-29.el6.i686 --setopt=protected_multilib=false
ok！