먼저 OS 버전을 확인한다. ubuntu@instance-20210304-1806:~$ lsb_release -a No LSB modules are available. Distributor ID:Ubuntu Description:Ubuntu 20.04.2 LTS Release:20.04 Codename:focal 마리아DB에 대한 apt 캐시 정책 확인 ubuntu@instance-20210304-1806:~$ sudo apt-cache policy mariadb-server mariadb-server: Installed: (none) Candidate: 1:10.3.25-0ubuntu0.20.04.1 Version table: 1:10.3.25-0ubuntu0.20.04.1 500 500 http://..