Error: Cannot open/read repomd.xml file for repository: rhel_*

普通用户运行yum search man后
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Error: Cannot open/read repomd.xml file for repository: rhel_*


之后死活不好，搜了半天也找不着原因，最后加上sudo竟然奇迹般的好了，在这之后不加sudo也没问题了！真是搞不懂