The following are the commands that you would beed to be aware and have a good handle.
- Commands
free
du / df
rsync
top
ps
lsof
uptime
dmesg
netstat
ss
strace
tcpdump
sar
vmstat
iostat
pidstat
mpstat
lscpu
uname
grep
find
sort
head
tail
basepath
realpath
tar
sed
awk
cut
tr
dig
nslookup
nc
traceroute
tracepath
ethtool
iperf
dd
ping
host
tracepath
ip
uniq
diff
ssh-keygen
ln
curl
wget
atop / htop
kill
fdisk
lsblk
mkfs
mount / umount