https://www.syu.ac.kr/blog/redhat-%ed%95%98%ec%9d%b4%eb%b8%8c%eb%a6%ac%eb%93%9c-%ed%81%b4%eb%9d%bc%ec%9a%b0%eb%93%9c-%ec%97%94%ec%a7%80%eb%8b%88%ec%96%b4-%ec%88%98%ea%b0%95%ec%83%9d-%eb%aa%a8%ec%a7%91/%ec%97%90%ed%8b%b0%eb%b2%84%ec%8a%a4%eb%9f%ac%eb%8b%9d-redhat-%ea%b0%84%ec%86%8c%ed%99%94_1/