Time Duration: 90 hours
ls, cd, pwd, treecp, mv,
rm, mkdir, rmdirchmod, chown, chgrp)cat, less, more, head,
tailgrep, find, locatetouch, nano, vi/vimdf, duuname, hostname, uptimeuseradd, usermod, passwdgroupadd, gpasswdsu, sudoapt (Debian/Ubuntu), yum/dnf (CentOS/Fedora)ps, top, htopkill, pkill, nice, renice
&, jobs, fg,
bgcron and atifconfig/ip aping, traceroute, netstatscp, rsyncufw, iptablestargzip, bzip2, zip, unzip
/var/log/syslog, /var/log/messages, dmesgfree, df, uptime,
vmstat