Working in the Linux terminal

Why it matters

When a cloud server misbehaves, there is no desktop to click. You connect, look around and fix things with commands. Interviewers for cloud support and DevOps roles often ask you to talk through a few commands, and the first weeks of most infrastructure jobs are spent in a terminal. If Linux basics or the command line are new to you, finish those lessons first.

Moving around and managing files

pwd              # where am I?
ls -la           # list files, including hidden
cd /var/log      # move into a folder
mkdir backups    # make a folder
cp a.txt b.txt   # copy a file
less syslog      # read a long file, q to quit

Users, permissions and sudo

Every file has an owner and permissions for read, write and execute. ls -l shows them as a string such as rwxr-x---: three letters for the owner, three for the group and three for everyone else. chmod changes permissions and chown changes the owner. Most admin tasks need , which runs one command with administrator rights. Use it only when needed; a careless command can break a server.