The Linux that cloud, DevOps and security engineers use every day on a modern systemd and bash system: files and permissions, processes and services, shell scripts, text tools, disks and finding performance problems.
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How Linux decides who can read, write and run a file: users and groups, rwx and octal modes, umask, ownership, the special bits and sudo.
42 total questions
Card #1
What do r, w and x mean on a directory?
Card #2
What are the octal values of r, w and x?
Card #3
What is the umask?
1. A file owned by root with mode 644 sits in ana's home directory (drwx------ ana). Can ana delete it with rm?
2. deploy.sh has mode 644. You run `./deploy.sh` and get "Permission denied". What would still run it without changing the mode?
3. A file has mode ----rwxrwx, owner ana, group dev. Ana is a member of dev. Can she read the file?
1. `chown ___ ana:dev /srv/app` changes the owner of the directory and of everything inside it.
Hint: A capital letter, for recursive.
2. Run `sudo ___` to see which commands you are allowed to run with sudo on this machine.
Hint: One letter, for list.
3. The ___ command prints the names of the groups a user belongs to.
Hint: The command is the plural of the thing it lists.
