Root @ DSQPC:/etc/apt# apt to get the update
Hit: 1 http://mirrors.aliyun.com/ubuntu focal InRelease
Hit: 2 http://mirrors.aliyun.com/ubuntu focal ws-security InRelease
Hit: 3 http://mirrors.aliyun.com/ubuntu focal - updates InRelease
Hit: 4 http://mirrors.aliyun.com/ubuntu focal - programs InRelease
Hit: 5 http://mirrors.aliyun.com/ubuntu focal - backports InRelease
Is reading package list... Complete the
Root @ DSQPC:/etc/apt# apt - get the install CAL
Is reading package list... Complete the
Are analyzing software package dependency tree
Is reading status information... Complete the
E: unable to locate the package CAL
Root @ DSQPC:/etc/apt# man CAL
No CAL manual page entry
Root @ DSQPC:/etc/apt#