ABDURROZAK.MY.ID // DEBIAN LINUX SERVER FUNDAMENTAL

MENGUASAI COMMAND LINEDEBIAN LINUX

Volume 03 dari seri Debian Linux Server Fundamental. Panduan komprehensif menguasai command line Linux dari dasar hingga mahir. Setiap command dijelaskan detail dengan syntax, parameter, contoh penggunaan, dan output. Dari navigasi direktori hingga administrasi server, semua dibahas tuntas dengan praktik langsung di terminal.

VOLUME03 / 17

SUB-BAB15

BACA150 MENIT

COMMAND100+

ABDUR ROZAK, S.Kom. Web Developer & System Administrator - abdurrozak.my.id

VOLUME 03 / 17

LINUX COMMAND LINE MASTERY

Panduan lengkap command line Linux untuk server administration. 15 sub-bab mencakup navigasi direktori, manipulasi file, text processing, pipe & redirect, permission, user management, process management, package management, service management, network commands, hingga praktik administrasi server. Setiap command disertai syntax, parameter, contoh, dan output.

SUB-BAB15 LEVELCommand Line WAKTU150 MENIT

SUB-BAB 01 TERMINAL

PENGENALAN TERMINAL

Apa Itu Terminal?

Terminal adalah interface berbasis teks untuk berinteraksi dengan sistem operasi. Di Linux, terminal adalah cara paling powerful untuk mengontrol sistem. Hampir semua administrasi server dilakukan via terminal.

TERMINAL EMULATOR

Program GUI yang menyediakan akses ke shell (GNOME Terminal, Konsole, xterm)

SHELL

Program yang menerima & menjalankan command (bash, zsh, fish)

CONSOLE

Terminal fisik (keyboard + monitor), TTY1-TTY6 di Linux

SSH

Remote terminal via network (Secure Shell)

Memahami Prompt

Saat buka terminal, kamu melihat prompt seperti ini:

admin@web-server:~

admin@web-server:~$ _

BAGIAN	ARTI	CONTOH
Username	User yang login	admin
@	Pemisah	@
Hostname	Nama server	web-server
:	Pemisah	:
~	Current directory (~ = home)	~ atau /home/admin
$	Ordinary user	$
#	Root user (superuser)	#

PENTING: Perhatikan simbol di akhir prompt! $ = ordinary user, # = root. Command berbahaya sebagai root bisa merusak sistem!

Shortcut Penting

SHORTCUT	FUNGSI
Tab	Auto-complete command/file/directory
Ctrl + C	Cancel/stop command yang sedang berjalan
Ctrl + Z	Suspend command (bisa dilanjut dengan fg/bg)
Ctrl + D	Logout / EOF
Ctrl + L	Clear screen (seperti `clear`)
Ctrl + A	Pindah ke awal baris
Ctrl + E	Pindah ke akhir baris
Ctrl + R	Search history command
↑ / ↓	Navigate history command
Ctrl + U	Hapus dari cursor ke awal baris
Ctrl + K	Hapus dari cursor ke akhir baris
Ctrl + W	Hapus kata sebelum cursor

Mendapatkan Bantuan

man

Manual pages - dokumentasi lengkap

man command

manual

admin@web-server:~$ man ls LS(1) User Commands LS(1) NAME ls - list directory contents SYNOPSIS ls [OPTION]... [FILE]... DESCRIPTION List information about the FILEs (the current directory by default). -a, --all do not ignore entries starting with . ... Manual page ls(1) line 1 (press h for help or q to quit)_

KEY	FUNGSI
`q`	Keluar dari man
`/`	Search dalam manual
`n`	Next match (setelah search)
`Space`	Page down
`b`	Page up
`h`	Help

--help

Quick help - ringkasan singkat

command --help

bash

admin@web-server:~$ ls --help Usage: ls [OPTION]... [FILE]... List information about the FILEs (the current directory by default). ... -a, --all do not ignore entries starting with . -l use a long listing format -h, --human-readable with -l, print sizes in human readable format ..._

whatis

Deskripsi singkat command

whatis command

bash

admin@web-server:~$ whatis ls ls (1) - list directory contents ls (1p) - list directory contents_

type

Cek jenis command (alias, builtin, external)

type command

bash

admin@web-server:~$ type ls ls is aliased to `ls --color=auto' admin@web-server:~$ type cd cd is a shell builtin admin@web-server:~$ type python3 python3 is /usr/bin/python3_

TIPS: Gunakan man untuk dokumentasi lengkap, --help untuk ringkasan cepat, whatis untuk deskripsi singkat.

KOMPETENSI SUB-BAB 01

Memahami perbedaan terminal, shell, console
Menghafal shortcut terminal penting
Mampu mendapatkan bantuan dengan man, --help, whatis

SUB-BAB 02 NAVIGATION

NAVIGASI DIREKTORI (ls, cd, pwd)

pwd - Print Working Directory

pwd

Tampilkan current directory

pwd [-L|-P]

OPTION	FUNGSI
`-L`	Logical - tampilkan path dengan symlink (default)
`-P`	Physical - tampilkan path fisik sebenarnya

bash

admin@web-server:~$ pwd /home/admin admin@web-server:~$ cd /var/log admin@web-server:/var/log$ pwd /var/log_

cd - Change Directory

Pindah directory

cd [directory]

PATH	ARTI	CONTOH
`cd` atau `cd ~`	Ke home directory	/home/admin
`cd ..`	Naik 1 level (parent)	dari /var/log ke /var
`cd ../..`	Naik 2 level	dari /var/log ke /
`cd -`	Ke directory sebelumnya	toggle between 2 last dirs
`cd /path`	Absolute path (dari root)	cd /etc/nginx
`cd dir`	Relative path (dari current)	cd documents

bash

admin@web-server:~$ cd /var/log admin@web-server:/var/log$ cd .. admin@web-server:/var$ cd - /var/log admin@web-server:/var/log$ cd admin@web-server:~$ cd ../.. admin@web-server:/$_

ls - List Directory Contents

List isi directory

ls [options] [directory]

OPTION	FUNGSI
`-l`	Long format (detail: permission, owner, size, date)
`-a`	All - termasuk hidden files (diawali .)
`-h`	Human-readable (size: KB, MB, GB)
`-t`	Sort by time (terbaru di atas)
`-S`	Sort by size (terbesar di atas)
`-r`	Reverse sort
`-R`	Recursive - list semua subdirectory
`-d`	Directory saja (bukan isi)
`-i`	Tampilkan inode number
`--color=auto`	Warnai output (directory=biru, exec=hijau)

bash

admin@web-server:~$ ls Desktop Documents Downloads Music Pictures Videos admin@web-server:~$ ls -la total 44 drwxr-xr-x 6 admin admin 4096 Sep 7 10:30 . drwxr-xr-x 3 root root 4096 Sep 7 09:00 .. -rw------- 1 admin admin 220 Sep 7 09:00 .bash_history -rw-r--r-- 1 admin admin 3771 Sep 7 09:00 .bashrc drwxr-xr-x 2 admin admin 4096 Sep 7 09:00 Desktop drwxr-xr-x 2 admin admin 4096 Sep 7 09:00 Documents admin@web-server:~$ ls -lh /var/log total 2.1M -rw-r--r-- 1 root root 45K Sep 7 10:30 syslog -rw-r----- 1 root adm 12K Sep 7 10:30 auth.log -rw-rw-r-- 1 root utmp 28K Sep 7 10:30 wtmp admin@web-server:~$ ls -lt total 44 drwxr-xr-x 2 admin admin 4096 Sep 7 10:30 Downloads drwxr-xr-x 2 admin admin 4096 Sep 7 10:25 Documents drwxr-xr-x 2 admin admin 4096 Sep 7 09:00 Desktop admin@web-server:~$ ls -lS total 44 drwxr-xr-x 2 admin admin 4096 Sep 7 10:30 Downloads drwxr-xr-x 2 admin admin 4096 Sep 7 10:25 Documents drwxr-xr-x 2 admin admin 4096 Sep 7 09:00 Desktop_

Memahami Output ls -l

output breakdown

Permission Breakdown

permission

- rwx r-x r-- ^ ^^^ ^^^ ^^^ | | | └─ other (semua orang lain) | | └─ group (group owner) | └─ user (owner) └─ file type (- = file, d = directory, l = symlink) r = read (4) w = write (2) x = execute (1) - = no permission (0)

TIPS: Kombinasi ls -lah adalah yang paling sering dipakai - menampilkan semua file dengan detail dan ukuran human-readable.

KOMPETENSI SUB-BAB 02

Mampu gunakan pwd untuk cek current directory
Mampu navigasi dengan cd (absolute, relative, ~, -, ..)
Mampu gunakan ls dengan berbagai option
Memahami output ls -l dan permission

SUB-BAB 03 INFO

INFO FILE & SISTEM

file - Identifikasi Tipe File

file

Identifikasi tipe file

file [options] filename

bash

admin@web-server:~$ file /etc/passwd /etc/passwd: ASCII text admin@web-server:~$ file /bin/ls /bin/ls: ELF 64-bit LSB pie executable, x86-64 admin@web-server:~$ file /var/log /var/log: directory admin@web-server:~$ file image.png image.png: PNG image data, 800 x 600, 8-bit/color RGBA_

stat - Detail File

stat

Detail info file (permission, size, time, inode)

stat filename

bash

admin@web-server:~$ stat /etc/passwd File: /etc/passwd Size: 2034 Blocks: 8 IO Block: 4096 regular file Device: 801h/2049d Inode: 131234 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Access: 2026-09-07 10:30:15.123456789 +0700 Modify: 2026-09-01 08:15:30.987654321 +0700 Change: 2026-09-01 08:15:30.987654321 +0700 Birth: -_

df - Disk Free

Lihat disk usage filesystem

df [options]

OPTION	FUNGSI
`-h`	Human-readable (KB, MB, GB)
`-H`	Human-readable (SI units, 1000-based)
`-T`	Tampilkan filesystem type
`-i`	Tampilkan inode usage
`-t type`	Filter by filesystem type

bash

admin@web-server:~$ df -h Filesystem Size Used Avail Use% Mounted on tmpfs 393M 1.4M 392M 1% /run /dev/sda2 19G 3.2G 15G 18% / tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock /dev/sda1 512M 5.8M 507M 2% /boot/efi tmpfs 393M 52K 393M 1% /run/user/1000 admin@web-server:~$ df -hT Filesystem Type Size Used Avail Use% Mounted on tmpfs tmpfs 393M 1.4M 392M 1% /run /dev/sda2 ext4 19G 3.2G 15G 18% / /dev/sda1 vfat 512M 5.8M 507M 2% /boot/efi_

du - Disk Usage

Lihat ukuran directory/file

du [options] [path]

OPTION	FUNGSI
`-h`	Human-readable
`-s`	Summary (total saja)
`-a`	All files (bukan hanya directory)
`--max-depth=N`	Depth level

bash

admin@web-server:~$ du -sh /var/log 45M /var/log admin@web-server:~$ du -sh /* 7.1M /bin 72M /boot 4.0K /cdrom 4.0K /dev 8.2M /etc 2.1G /home 650M /usr 380M /var admin@web-server:~$ du -sh /var/* --max-depth=0 12K /var/backups 45M /var/cache 45M /var/log 12M /var/lib_

free - Memory Usage

free

Lihat memory (RAM & swap) usage

free [options]

bash

admin@web-server:~$ free -h total used free shared buff/cache available Mem: 1.9Gi 220Mi 1.4Gi 4.0Mi 320Mi 1.6Gi Swap: 2.0Gi 0B 2.0Gi_

uptime - System Uptime

uptime

Lihat uptime & load average

uptime

bash

admin@web-server:~$ uptime 10:30:15 up 5 days, 3:15, 1 user, load average: 0.08, 0.03, 0.01_

FIELD	ARTI
10:30:15	Current time
up 5 days, 3:15	Uptime (sudah nyala 5 hari 3 jam 15 menit)
1 user	Jumlah user yang login
load average	Average load (1, 5, 15 menit terakhir)

KOMPETENSI SUB-BAB 03

Mampu identifikasi tipe file dengan file
Mampu lihat detail file dengan stat
Mampu cek disk usage dengan df dan du
Mampu cek memory dengan free
Mampu cek uptime & load average

SUB-BAB 04 FILE OPS

MANIPULASI FILE & DIRECTORY

mkdir - Make Directory

mkdir

Buat directory baru

mkdir [options] directory

OPTION	FUNGSI
`-p`	Buat parent directory jika belum ada
`-m`	Set permission saat buat
`-v`	Verbose (tampilkan pesan)

bash

admin@web-server:~$ mkdir projects admin@web-server:~$ mkdir -p projects/web/frontend mkdir: created directory 'projects/web' mkdir: created directory 'projects/web/frontend' admin@web-server:~$ mkdir -m 755 scripts admin@web-server:~$ ls -ld scripts drwxr-xr-x 2 admin admin 4096 Sep 7 10:30 scripts_

touch - Buat File Kosong

touch

Buat file kosong atau update timestamp

touch [options] filename

bash

admin@web-server:~$ touch file.txt admin@web-server:~$ touch file1.txt file2.txt file3.txt admin@web-server:~$ ls -l file.txt -rw-r--r-- 1 admin admin 0 Sep 7 10:30 file.txt_

cp - Copy

Copy file atau directory

cp [options] source destination

OPTION	FUNGSI
`-r` atau `-R`	Recursive (untuk directory)
`-i`	Interactive (tanya sebelum overwrite)
`-v`	Verbose (tampilkan progress)
`-p`	Preserve attributes (permission, timestamp)
`-a`	Archive (sama dengan -dR --preserve=all)
`-u`	Update (copy hanya jika source lebih baru)

bash

admin@web-server:~$ cp file.txt backup.txt admin@web-server:~$ cp -r projects/ backup-projects/ admin@web-server:~$ cp -i file.txt existing.txt cp: overwrite 'existing.txt'? y admin@web-server:~$ cp -v file.txt /tmp/ 'file.txt' -> '/tmp/file.txt'_

mv - Move/Rename

Move atau rename file/directory

mv [options] source destination

bash

admin@web-server:~$ mv old.txt new.txt # Rename file admin@web-server:~$ mv file.txt /tmp/ # Move file ke /tmp/ admin@web-server:~$ mv -i file.txt existing.txt mv: overwrite 'existing.txt'? y_

rm - Remove

Hapus file atau directory

rm [options] filename

OPTION	FUNGSI
`-r` atau `-R`	Recursive (untuk directory)
`-f`	Force (tidak tanya konfirmasi)
`-i`	Interactive (tanya sebelum hapus)
`-v`	Verbose (tampilkan progress)
`-rf`	Recursive + Force (HATI-HATI!)

bash

admin@web-server:~$ rm file.txt admin@web-server:~$ rm -r directory/ admin@web-server:~$ rm -i file.txt rm: remove regular file 'file.txt'? y admin@web-server:~$ rm -rf directory/ # HATI-HATI! Hapus tanpa tanya!_

PERINGATAN: rm -rf sangat berbahaya! Salah ketik bisa hapus data penting. Selalu double-check path. Pertimbangkan pakai rm -ri untuk safety.

ln - Link

Buat link (hard link atau symlink)

ln [options] target [link_name]

bash

admin@web-server:~$ ln file.txt hardlink.txt # Buat hard link admin@web-server:~$ ln -s file.txt symlink.txt # Buat symbolic link (shortcut) admin@web-server:~$ ls -l -rw-r--r-- 2 admin admin 1234 Sep 7 10:30 file.txt -rw-r--r-- 2 admin admin 1234 Sep 7 10:30 hardlink.txt lrwxrwxrwx 1 admin admin 8 Sep 7 10:30 symlink.txt -> file.txt_

KOMPETENSI SUB-BAB 04

Mampu buat directory dengan mkdir (termasuk -p)
Mampu buat file kosong dengan touch
Mampu copy dengan cp (file & directory)
Mampu move/rename dengan mv
Mampu hapus dengan rm
Membedakan hard link dan symlink

SUB-BAB 05 VIEWING

VIEWING FILE

cat - Concatenate

cat

Tampilkan isi file atau gabungkan file

cat [options] file

OPTION	FUNGSI
`-n`	Nomori baris
`-b`	Nomori baris non-blank
`-s`	Squeeze blank lines

bash

admin@web-server:~$ cat file.txt Line 1 Line 2 Line 3 admin@web-server:~$ cat -n file.txt 1 Line 1 2 Line 2 3 Line 3 admin@web-server:~$ cat file1.txt file2.txt > combined.txt # Gabungkan 2 file ke file baru_

less - Pager

less

Lihat file dengan pager (scroll up/down)

less file

KEY	FUNGSI
`Space` atau `f`	Page down
`b`	Page up
`g`	Go to first line
`G`	Go to last line
`/pattern`	Search forward
`?pattern`	Search backward
`n`	Next match
`N`	Previous match
`q`	Quit
`h`	Help

less /var/log/syslog

Sep 7 10:30:15 web-server systemd[1]: Started Session 1 of User admin. Sep 7 10:30:16 web-server kernel: [ 123.456] EXT4-fs (sda2): mounted Sep 7 10:30:17 web-server sshd[1234]: Server listening on 0.0.0.0 port 22 ... /var/log/syslog (END)_

head - Awal File

head

Tampilkan awal file

head [options] file

bash

admin@web-server:~$ head /etc/passwd root:x:0:0:root:/root:/bin/bash daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin bin:x:2:2:bin:/bin:/usr/sbin/nologin sys:x:3:3:sys:/dev:/usr/sbin/nologin sync:x:4:65534:sync:/bin:/bin/sync games:x:5:60:games:/usr/games:/usr/sbin/nologin man:x:6:12:man:/var/cache/man:/usr/sbin/nologin lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin mail:x:8:8:mail:/var/mail:/usr/sbin/nologin news:x:9:9:news:/var/spool/news:/usr/sbin/nologin admin@web-server:~$ head -n 5 /etc/passwd root:x:0:0:root:/root:/bin/bash daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin bin:x:2:2:bin:/bin:/usr/sbin/nologin sys:x:3:3:sys:/dev:/usr/sbin/nologin sync:x:4:65534:sync:/bin:/bin/sync_

tail - Akhir File

tail

Tampilkan akhir file

tail [options] file

OPTION	FUNGSI
`-n N`	Tampilkan N baris terakhir
`-f`	Follow - tampilkan baris baru real-time
`-F`	Like -f, tapi retry jika file di-recreate

bash

admin@web-server:~$ tail -n 5 /var/log/syslog Sep 7 10:30:11 web-server systemd[1]: Started Session 1. Sep 7 10:30:12 web-server kernel: [ 123.456] EXT4-fs mounted Sep 7 10:30:13 web-server sshd[1234]: Server listening on 0.0.0.0 Sep 7 10:30:14 web-server sshd[1234]: Server listening on :: port 22 Sep 7 10:30:15 web-server systemd[1]: Started OpenBSD Secure Shell admin@web-server:~$ tail -f /var/log/syslog # Real-time monitoring - tekan Ctrl+C untuk stop Sep 7 10:30:16 web-server kernel: new message... Sep 7 10:30:17 web-server systemd: another message... ^C_

TIPS: tail -f sangat berguna untuk monitoring log real-time saat troubleshooting.

KOMPETENSI SUB-BAB 05

Mampu tampilkan isi file dengan cat
Mampu browse file dengan less
Mampu lihat awal file dengan head
Mampu lihat akhir file dengan tail (termasuk -f)

SUB-BAB 06 EDITOR

TEXT EDITOR (nano)

nano - Simple Text Editor

nano adalah text editor sederhana yang user-friendly. Cocok untuk pemula karena shortcut ditampilkan di bagian bawah layar.

nano

Edit text file

nano [options] [file]

OPTION	FUNGSI
`-l`	Tampilkan line numbers
`-m`	Enable mouse support
`-w`	Disable line wrapping
`-B`	Backup file saat save

nano config.txt

GNU nano 6.2 config.txt This is a config file Line 2 of the file Line 3 with some text ^G Help ^O Write Out ^W Where Is ^K Cut ^T Execute ^X Exit ^R Read File ^\ Replace ^U Paste ^J Justify_

Shortcut Penting nano

SHORTCUT	FUNGSI
Ctrl + O	Save (Write Out)
Ctrl + X	Exit (dengan prompt save jika ada perubahan)
Ctrl + K	Cut line
Ctrl + U	Paste (Uncut)
Ctrl + W	Search (Where Is)
Ctrl + \	Replace
Ctrl + _	Go to line number
Ctrl + G	Help
Alt + A	Start selection (untuk cut/copy)
Alt + 6	Copy selection
Alt + T	Cut selection

TIPS: Untuk editor yang lebih advanced, pelajari vim atau emacs. Tapi untuk pemula, nano sudah cukup untuk sebagian besar tugas.

KOMPETENSI SUB-BAB 06

Mampu buka dan edit file dengan nano
Menghafal shortcut nano penting
Mampu save dan exit dengan benar

SUB-BAB 07 SEARCH

SEARCH & FIND

grep - Search Text in Files

grep

Global Regular Expression Print - cari text dalam file

grep [options] pattern file

OPTION	FUNGSI
`-i`	Case-insensitive
`-r` atau `-R`	Recursive (cari di semua file dalam directory)
`-n`	Tampilkan nomor baris
`-v`	Invert match (tampilkan baris yang TIDAK match)
`-c`	Count (hitung jumlah match)
`-l`	List files with matches
`-w`	Match whole word
`-E`	Extended regex

bash

admin@web-server:~$ grep "error" /var/log/syslog Sep 7 10:30:15 web-server kernel: error in module Sep 7 10:30:16 web-server app: error occurred admin@web-server:~$ grep -i "ERROR" /var/log/syslog # Case-insensitive, match ERROR, error, Error, dll admin@web-server:~$ grep -rn "error" /var/log/ /var/log/syslog:15:error in module /var/log/syslog:16:error occurred /var/log/auth.log:5:authentication error admin@web-server:~$ grep -c "error" /var/log/syslog 15 admin@web-server:~$ grep -l "error" /var/log/* /var/log/syslog /var/log/auth.log admin@web-server:~$ grep -v "info" /var/log/syslog # Tampilkan baris yang TIDAK mengandung "info"_

find - Cari File

find

Cari file berdasarkan kriteria

find path [options] [expression]

OPTION	FUNGSI
`-name pattern`	Cari berdasarkan nama (case-sensitive)
`-iname pattern`	Cari berdasarkan nama (case-insensitive)
`-type f`	File saja
`-type d`	Directory saja
`-size +N`	Ukuran lebih dari N (c=bytes, k=KB, M=MB, G=GB)
`-mtime +N`	Dimodifikasi lebih dari N hari lalu
`-user username`	File milik user tertentu
`-exec cmd {} \;`	Jalankan command pada hasil

bash

admin@web-server:~$ find /home -name "*.txt" /home/admin/file.txt /home/admin/docs/readme.txt admin@web-server:~$ find / -type f -size +100M /var/log/large-file.log /var/lib/docker/image/... admin@web-server:~$ find /var/log -mtime +7 # File yang dimodifikasi lebih dari 7 hari lalu admin@web-server:~$ find /tmp -type f -delete # Hapus semua file di /tmp (HATI-HATI!) admin@web-server:~$ find /home -name "*.log" -exec ls -lh {} \; -rw-r--r-- 1 admin admin 1.2M Sep 7 10:30 /home/admin/app.log_

which & whereis

which

Lokasi executable command

which command

bash

admin@web-server:~$ which python3 /usr/bin/python3 admin@web-server:~$ which ls /usr/bin/ls_

whereis

Lokasi binary, source, dan manual page

whereis command

bash

admin@web-server:~$ whereis python3 python3: /usr/bin/python3 /usr/lib/python3 /usr/share/man/man1/python3.1.gz_

KOMPETENSI SUB-BAB 07

Mampu cari text dalam file dengan grep
Mampu cari file dengan find
Mampu cari lokasi executable dengan which dan whereis

SUB-BAB 08 PIPE

PIPE & REDIRECT

Pipe (|)

Pipe menghubungkan output satu command sebagai input command berikutnya. Ini memungkinkan kombinasi command untuk tugas kompleks.

Pipe - output jadi input command berikutnya

command1 | command2 | command3

bash

admin@web-server:~$ ls -l | grep ".txt" # List semua file, lalu filter hanya yang .txt admin@web-server:~$ ps aux | grep nginx # List process, cari yang nginx admin@web-server:~$ cat file.txt | sort | uniq -c | sort -nr # Sort → unik → count → sort by count descending admin@web-server:~$ ls -l | sort -k5 -n -r | head -5 # Sort by size (kolom 5), numeric, reverse, tampilkan 5 teratas_

Redirection

>, >>, 2>

Redirect output/error ke file

command > file # stdout ke file (overwrite) command >> file # stdout ke file (append) command 2> file # stderr ke file command > file 2>&1 # stdout & stderr ke file yang sama command &> file # stdout & stderr ke file (shortcut) command < file # input dari file

bash

admin@web-server:~$ ls -l > files.txt # Output ls disimpan ke files.txt admin@web-server:~$ echo "new line" >> files.txt # Tambahkan baris ke akhir file admin@web-server:~$ find / -name "*.log" 2> errors.txt # Error (permission denied) disimpan ke errors.txt admin@web-server:~$ sort file.txt | uniq > unique.txt # Sort file, unik, simpan ke unique.txt_

tee - Output ke Screen DAN File

tee

Output ke screen dan simpan ke file sekaligus

command | tee file

bash

admin@web-server:~$ ls -l | tee files.txt # Tampilkan di screen DAN simpan ke files.txt admin@web-server:~$ ls -l | tee -a files.txt # -a = append (tambahkan ke file)_

xargs - Execute Command dari Input

xargs

Build dan execute command dari standard input

command | xargs command

bash

admin@web-server:~$ find . -name "*.log" | xargs rm # Cari file .log, lalu hapus satu per satu admin@web-server:~$ echo "file1 file2 file3" | xargs touch # Buat 3 file sekaligus admin@web-server:~$ cat files.txt | xargs -I {} cp {} /backup/ # Copy setiap file di files.txt ke /backup/_

KOMPETENSI SUB-BAB 08

Mampu gunakan pipe untuk chaining command
Mampu redirect output/error ke file
Mampu gunakan tee untuk output ke screen dan file
Mampu gunakan xargs untuk execute command dari input

SUB-BAB 09 PERMISSION

PERMISSION (chmod, chown, chgrp)

Memahami Permission

permission breakdown

chmod - Change Mode

chmod

Ubah permission file/directory

chmod [options] mode file

Metode 1: Numeric (octal)

bash

admin@web-server:~$ chmod 755 script.sh # 7 = rwx (owner), 5 = r-x (group), 5 = r-x (other) admin@web-server:~$ chmod 644 file.txt # 6 = rw- (owner), 4 = r-- (group), 4 = r-- (other) admin@web-server:~$ chmod 700 private-dir/ # Hanya owner yang bisa akses admin@web-server:~$ chmod 600 secret.txt # Hanya owner bisa read/write_

Metode 2: Symbolic

bash

admin@web-server:~$ chmod u+x script.sh # u = user (owner), +x = tambah execute admin@web-server:~$ chmod g-w file.txt # g = group, -w = hapus write admin@web-server:~$ chmod o=r file.txt # o = other, =r = set read only admin@web-server:~$ chmod a+x script.sh # a = all (u+g+o), +x = tambah execute untuk semua admin@web-server:~$ chmod u=rwx,g=rx,o=r file.txt # Set sekaligus: owner=rwx, group=rx, other=r_

Permission Umum

PERMISSION	NUMERIC	USE CASE
rw-r--r--	644	File biasa
rwxr-xr-x	755	Directory, executable
rw-------	600	File privat
rwx------	700	Directory privat
rw-r-----	640	File group-restricted
rwxrwxr-x	775	Collaborative directory

chown - Change Owner

chown

Ubah owner dan/atau group file

chown [options] owner[:group] file

bash

admin@web-server:~$ sudo chown newuser file.txt # Ubah owner menjadi newuser admin@web-server:~$ sudo chown newuser:newgroup file.txt # Ubah owner DAN group sekaligus admin@web-server:~$ sudo chown :newgroup file.txt # Ubah group saja (owner tetap) admin@web-server:~$ sudo chown -R newuser:newgroup directory/ # -R = recursive, terapkan ke semua isi directory_

chgrp - Change Group

chgrp

Ubah group file

chgrp [options] group file

bash

admin@web-server:~$ sudo chgrp developers project/ # Ubah group menjadi developers admin@web-server:~$ sudo chgrp -R developers project/ # -R = recursive_

KOMPETENSI SUB-BAB 09

Memahami sistem permission Linux (rwx)
Mampu gunakan chmod (numeric & symbolic)
Mampu gunakan chown dan chgrp
Tahu permission umum untuk file & directory

SUB-BAB 10 USER

USER & GROUP MANAGEMENT

User Management

useradd

Buat user baru

useradd [options] username

OPTION	FUNGSI
`-m`	Buat home directory
`-s /bin/bash`	Set default shell
`-g group`	Set primary group
`-G group1,group2`	Tambah ke group tambahan
`-c "comment"`	Full name/comment

bash

admin@web-server:~$ sudo useradd -m -s /bin/bash newuser # Buat user dengan home directory dan bash shell admin@web-server:~$ sudo useradd -m -s /bin/bash -G sudo,developers john # Buat user john, tambah ke group sudo dan developers admin@web-server:~$ sudo passwd newuser New password: •••••••• Retype new password: •••••••• passwd: password updated successfully_

usermod

Modifikasi user

usermod [options] username

bash

admin@web-server:~$ sudo usermod -aG sudo username # Tambah user ke group sudo admin@web-server:~$ sudo usermod -s /bin/zsh username # Ganti shell user admin@web-server:~$ sudo usermod -L username # Lock account (tidak bisa login) admin@web-server:~$ sudo usermod -U username # Unlock account admin@web-server:~$ sudo usermod -e 2026-12-31 username # Set expiration date_

userdel

Hapus user

userdel [options] username

bash

admin@web-server:~$ sudo userdel username # Hapus user (home directory tetap ada) admin@web-server:~$ sudo userdel -r username # -r = hapus home directory juga_

Group Management

groupadd / groupdel

Buat/hapus group

groupadd groupname groupdel groupname

bash

admin@web-server:~$ sudo groupadd developers # Buat group baru admin@web-server:~$ sudo groupdel developers # Hapus group_

Info User & Group

id, whoami, groups

Info user yang login

bash

admin@web-server:~$ whoami admin admin@web-server:~$ id uid=1000(admin) gid=1000(admin) groups=1000(admin),27(sudo) admin@web-server:~$ id username uid=1001(username) gid=1001(username) groups=1001(username) admin@web-server:~$ groups admin sudo admin@web-server:~$ groups username username : username developers_

KOMPETENSI SUB-BAB 10

Mampu menambah, modifikasi, dan hapus user
Mampu menambah, modifikasi, dan hapus group
Mampu cek info user dan group

SUB-BAB 11 PROCESS

PROCESS MANAGEMENT

ps - Process Status

Lihat process yang berjalan

ps [options]

OPTION	FUNGSI
`aux`	Semua process, semua user, dengan detail
`-ef`	Full format, semua process
`-u username`	Process milik user tertentu

bash

admin@web-server:~$ ps aux USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 1 0.0 0.4 169344 11520 ? Ss 10:00 0:02 /sbin/init root 2 0.0 0.0 0 0 ? S 10:00 0:00 [kthreadd] root 456 0.0 0.5 72340 5640 ? Ss 10:00 0:00 /usr/sbin/sshd admin 1234 0.0 0.3 21568 3456 pts/0 Ss 10:30 0:00 -bash admin 1456 0.0 0.2 38120 3200 pts/0 R+ 10:35 0:00 ps aux admin@web-server:~$ ps aux | grep nginx root 1234 0.0 0.5 72340 5640 ? Ss 10:00 0:00 nginx: master www-data 1235 0.0 0.3 72540 3456 ? S 10:00 0:00 nginx: worker_

top - Real-time Process Monitor

top

Real-time process monitor (interactive)

top

top - 10:30:15 up 5 days, 3:15, 1 user, load average: 0.08, 0.03, 0.01 Tasks: 120 total, 1 running, 119 sleeping, 0 stopped, 0 zombie %Cpu(s): 2.3 us, 1.0 sy, 0.0 ni, 96.5 id, 0.2 wa, 0.0 hi, 0.0 si MiB Mem : 1987.2 total, 1456.8 free, 220.4 used, 310.0 buff/cache MiB Swap: 2048.0 total, 2048.0 free, 0.0 used. 1650.4 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1234 root 20 0 72340 5640 4560 S 0.3 0.3 0:00.45 sshd 1456 admin 20 0 21568 3456 2800 R 0.3 0.2 0:00.12 top Commands: h/? : help q : quit k : kill r : renice M : sort by MEM P : sort by CPU T : sort by TIME_

KEY	FUNGSI
`q`	Keluar
`k`	Kill process (masukkan PID)
`r`	Renice process (ubah priority)
`M`	Sort by memory usage
`P`	Sort by CPU usage
`T`	Sort by time
`h` atau `?`	Help
`Space`	Refresh

kill - Terminate Process

kill

Kirim signal ke process

kill [-signal] PID

bash

admin@web-server:~$ kill 1234 # Kirim SIGTERM (signal 15) - graceful termination admin@web-server:~$ kill -9 1234 # Kirim SIGKILL (signal 9) - force kill admin@web-server:~$ kill -SIGTERM 1234 # Sama dengan kill 1234_

SIGNAL	NUMBER	DESKRIPSI
`SIGTERM`	15	Graceful termination (default)
`SIGKILL`	9	Force kill (tidak bisa di-catch)
`SIGHUP`	1	Hangup (reload config)
`SIGINT`	2	Interrupt (Ctrl+C)
`SIGSTOP`	17	Stop process
`SIGCONT`	19	Continue stopped process

killall & pkill

killall, pkill

Kill process by name

bash

admin@web-server:~$ killall nginx # Kill semua process bernama nginx admin@web-server:~$ pkill nginx # Kill process yang match pattern "nginx" admin@web-server:~$ pkill -u username # Kill semua process milik user_

Background & Foreground

bg, fg, jobs

Manage background/foreground process

bash

admin@web-server:~$ long-running-command & [1] 1234 # Jalankan di background (& di akhir) admin@web-server:~$ jobs [1]+ Running long-running-command & admin@web-server:~$ fg %1 # Bawa job 1 ke foreground admin@web-server:~$ Ctrl+Z [1]+ Stopped long-running-command # Suspend process (Ctrl+Z) admin@web-server:~$ bg %1 # Lanjutkan di background_

KOMPETENSI SUB-BAB 11

Mampu lihat process dengan ps
Mampu monitor real-time dengan top
Mampu kill process dengan kill/killall/pkill
Mampu manage background/foreground process

SUB-BAB 12 PACKAGE

PACKAGE MANAGEMENT (apt)

apt - Advanced Package Tool

apt

Package manager Debian

bash

# Update package list admin@web-server:~$ sudo apt update Hit:1 http://deb.debian.org/debian bookworm InRelease Hit:2 http://deb.debian.org/debian bookworm-updates InRelease Hit:3 http://security.debian.org bookworm-security InRelease Reading package lists... Done Building dependency tree... Done # Upgrade packages admin@web-server:~$ sudo apt upgrade -y Reading package lists... Done The following packages will be upgraded: package1 package2 package3 3 upgraded, 0 newly installed, 0 to remove # Install package admin@web-server:~$ sudo apt install nginx -y Reading package lists... Done The following NEW packages will be installed: nginx nginx-common # Remove package admin@web-server:~$ sudo apt remove nginx # Remove package (config files tetap ada) admin@web-server:~$ sudo apt purge nginx # Remove package + config files # Autoremove (hapus dependency tidak terpakai) admin@web-server:~$ sudo apt autoremove -y # Search package admin@web-server:~$ apt search nginx # Info package admin@web-server:~$ apt show nginx # List installed packages admin@web-server:~$ apt list --installed_

TIPS: Selalu jalankan apt update sebelum apt install atau apt upgrade untuk memastikan package list terbaru.

KOMPETENSI SUB-BAB 12

Mampu update package list dengan apt update
Mampu upgrade packages dengan apt upgrade
Mampu install dan remove packages
Mampu search dan info package

SUB-BAB 13 SERVICE

SERVICE MANAGEMENT (systemctl)

systemctl - Control systemd

systemctl

Control systemd system and service manager

bash

# Start service admin@web-server:~$ sudo systemctl start nginx # Stop service admin@web-server:~$ sudo systemctl stop nginx # Restart service admin@web-server:~$ sudo systemctl restart nginx # Reload configuration (tanpa restart) admin@web-server:~$ sudo systemctl reload nginx # Status service admin@web-server:~$ systemctl status nginx ● nginx.service - A high performance web server and a reverse proxy server Loaded: loaded (/lib/systemd/system/nginx.service; enabled) Active: active (running) since Mon 2026-09-07 10:30:15 WIB; 5min ago Docs: man:nginx(8) Process: 1234 ExecStartPre=/usr/sbin/nginx -t (code=exited, status=0/SUCCESS) Process: 1235 ExecStart=/usr/sbin/nginx (code=exited, status=0/SUCCESS) Main PID: 1236 (nginx) Tasks: 3 (limit: 2340) Memory: 5.2M CPU: 123ms CGroup: /system.slice/nginx.service # Enable service (start on boot) admin@web-server:~$ sudo systemctl enable nginx Created symlink /etc/systemd/system/multi-user.target.wants/nginx.service # Disable service (tidak start on boot) admin@web-server:~$ sudo systemctl disable nginx # List all services admin@web-server:~$ systemctl list-units --type=service # List failed services admin@web-server:~$ systemctl --failed_

journalctl - View Logs

journalctl

View systemd journal logs

bash

# Lihat semua logs admin@web-server:~$ journalctl # Log untuk service tertentu admin@web-server:~$ journalctl -u nginx # Real-time logs admin@web-server:~$ journalctl -f # Logs dari 1 jam terakhir admin@web-server:~$ journalctl --since "1 hour ago" # Logs hari ini admin@web-server:~$ journalctl --since today # Logs dengan priority tertentu admin@web-server:~$ journalctl -p err # err = error, warning, notice, info, debug_

KOMPETENSI SUB-BAB 13

Mampu start/stop/restart/reload service
Mampu enable/disable service
Mampu cek status service
Mampu lihat logs dengan journalctl

SUB-BAB 14 NETWORK

NETWORK COMMANDS

ip - Network Configuration

Show/manipulate routing, network devices, interfaces

bash

# Lihat IP address admin@web-server:~$ ip addr show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 inet 127.0.0.1/8 scope host lo 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 inet 192.168.1.10/24 brd 192.168.1.255 scope global eth0 # Shortcut admin@web-server:~$ ip a # Lihat routing table admin@web-server:~$ ip route show default via 192.168.1.1 dev eth0 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.10 # Shortcut admin@web-server:~$ ip r # Lihat link status admin@web-server:~$ ip link show_

Connectivity Testing

ping

Test connectivity ke host

bash

admin@web-server:~$ ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data. 64 bytes from 8.8.8.8: icmp_seq=1 ttl=117 time=12.3 ms 64 bytes from 8.8.8.8: icmp_seq=2 ttl=117 time=11.8 ms ^C --- 8.8.8.8 ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 1001ms rtt min/avg/max/mdev = 11.8/12.0/12.3/0.2 ms admin@web-server:~$ ping -c 4 google.com # -c 4 = kirim 4 packet saja_

traceroute

Lihat route ke tujuan

bash

admin@web-server:~$ traceroute google.com traceroute to google.com (142.250.1.100), 30 hops max, 60 byte packets 1 192.168.1.1 (192.168.1.1) 1.234 ms 1.123 ms 1.098 ms 2 10.0.0.1 (10.0.0.1) 5.678 ms 5.456 ms 5.321 ms 3 * * * 4 142.250.1.100 (142.250.1.100) 12.345 ms 12.123 ms 12.098 ms_

dig, nslookup

DNS lookup

bash

admin@web-server:~$ dig google.com ; <<>> DiG 9.18 <<>> google.com ;; ANSWER SECTION: google.com. 300 IN A 142.250.1.100 admin@web-server:~$ nslookup google.com Server: 8.8.8.8 Address: 8.8.8.8#53 Non-authoritative answer: Name: google.com Address: 142.250.1.100_

ss, netstat

Lihat network connections & ports

bash

admin@web-server:~$ ss -tulpn Netid State Recv-Q Send-Q Local Address:Port Peer Address:Port Process tcp LISTEN 0 128 0.0.0.0:22 0.0.0.0:* users:(("sshd",pid=456)) tcp LISTEN 0 128 0.0.0.0:80 0.0.0.0:* users:(("nginx",pid=1234)) admin@web-server:~$ netstat -tulpn # netstat sudah deprecated, gunakan ss_

KOMPETENSI SUB-BAB 14

Mampu lihat IP address dan routing dengan ip
Mampu test connectivity dengan ping
Mampu trace route dengan traceroute
Mampu DNS lookup dengan dig/nslookup
Mampu lihat network connections dengan ss

SUB-BAB 15 PRAKTIK

PRAKTIK ADMINISTRASI

Skenario 1: Setup Web Server

BASH

# 1. Update sistem
sudo apt update && sudo apt upgrade -y

# 2. Install nginx
sudo apt install nginx -y

# 3. Start & enable nginx
sudo systemctl start nginx
sudo systemctl enable nginx

# 4. Cek status
sudo systemctl status nginx

# 5. Cek port
sudo ss -tulpn | grep :80

# 6. Test dari browser
# Buka http://server-ip

# 7. Edit default page
sudo nano /var/www/html/index.html

# 8. Allow di firewall
sudo ufw allow 'Nginx HTTP'

Skenario 2: Setup User & SSH

BASH

# 1. Buat user baru
sudo useradd -m -s /bin/bash -G sudo newuser

# 2. Set password
sudo passwd newuser

# 3. Install SSH server
sudo apt install openssh-server -y

# 4. Start & enable SSH
sudo systemctl start ssh
sudo systemctl enable ssh

# 5. Edit SSH config (security)
sudo nano /etc/ssh/sshd_config
# Ubah: Port 2222, PermitRootLogin no

# 6. Restart SSH
sudo systemctl restart ssh

# 7. Allow SSH di firewall
sudo ufw allow 2222/tcp

# 8. Test SSH dari client
ssh -p 2222 newuser@server-ip

Skenario 3: Monitoring & Troubleshooting

BASH

# 1. Cek system info
uname -a
lsb_release -a
uptime
free -h
df -h

# 2. Cek process
top
ps aux | grep nginx

# 3. Cek network
ip addr show
ip route show
ss -tulpn

# 4. Cek logs
journalctl -u nginx
journalctl -p err --since "1 hour ago"

# 5. Test connectivity
ping -c 4 8.8.8.8
ping -c 4 google.com
dig google.com
traceroute google.com

# 6. Cek service
systemctl status nginx
systemctl status ssh

# 7. Cek disk usage
du -sh /var/log/*
du -sh /var/www/*

Checklist Harian Administrator

TUGAS	COMMAND	FREKUENSI
Cek uptime	uptime	Harian
Cek disk usage	df -h	Harian
Cek memory	free -h	Harian
Update sistem	sudo apt update && sudo apt upgrade	Mingguan
Cek logs	journalctl -p err --since "1 day ago"	Harian
Cek service	systemctl --failed	Harian
Backup	Custom backup script	Harian/Mingguan
Security audit	sudo lynis audit system	Bulanan

SELAMAT! Kamu telah menyelesaikan Volume 03 - Linux Command Line Mastery. Dari navigasi direktori hingga administrasi server, kamu sekarang menguasai command line Linux. Di Volume 04, kita akan dalami File System & Storage Management lebih mendalam. Sampai jumpa!

KOMPETENSI SUB-BAB 15

Mampu setup web server dari nol
Mampu setup user & SSH
Mampu monitoring & troubleshooting
Memahami checklist harian administrator

VOLUME 03 SELESAI

SELAMAT!

Kamu telah menyelesaikan Volume 03 - Linux Command Line Mastery. 15 sub-bab dari pengenalan terminal hingga praktik administrasi server. Kamu sekarang menguasai command line Linux dengan 100+ command. Di Volume 04, kita akan dalami File System & Storage Management. Sampai jumpa!

SUB-BAB15 COMMAND100+ NEXTFile System

ABDURROZAK.MY.ID // TERHUBUNG

JARINGAN SOSIAL

Temukan saya di berbagai platform digital

s.id GitHub Instagram Threads Facebook TikTok YT Teacher YT Course YT Studio Hashnode WhatsApp Email

MENGUASAI COMMAND LINEDEBIAN LINUX

LINUX COMMAND LINE MASTERY

PENGENALAN TERMINAL

Apa Itu Terminal?

Memahami Prompt

Shortcut Penting

Mendapatkan Bantuan

NAVIGASI DIREKTORI (ls, cd, pwd)

pwd - Print Working Directory

cd - Change Directory

ls - List Directory Contents

Memahami Output ls -l

Permission Breakdown

INFO FILE & SISTEM

file - Identifikasi Tipe File

stat - Detail File

df - Disk Free

du - Disk Usage

free - Memory Usage

uptime - System Uptime

MANIPULASI FILE & DIRECTORY

mkdir - Make Directory

touch - Buat File Kosong

cp - Copy

mv - Move/Rename

rm - Remove

ln - Link

VIEWING FILE

cat - Concatenate

less - Pager

head - Awal File

tail - Akhir File

TEXT EDITOR (nano)

nano - Simple Text Editor

Shortcut Penting nano

SEARCH & FIND

grep - Search Text in Files

find - Cari File

which & whereis

PIPE & REDIRECT

Pipe (|)

Redirection

tee - Output ke Screen DAN File

xargs - Execute Command dari Input

PERMISSION (chmod, chown, chgrp)

Memahami Permission

chmod - Change Mode

Metode 1: Numeric (octal)

Metode 2: Symbolic

Permission Umum

chown - Change Owner

chgrp - Change Group

USER & GROUP MANAGEMENT

User Management

Group Management

Info User & Group

PROCESS MANAGEMENT

ps - Process Status

top - Real-time Process Monitor

kill - Terminate Process

killall & pkill

Background & Foreground

PACKAGE MANAGEMENT (apt)

apt - Advanced Package Tool

SERVICE MANAGEMENT (systemctl)

systemctl - Control systemd

journalctl - View Logs

NETWORK COMMANDS

ip - Network Configuration

Connectivity Testing

PRAKTIK ADMINISTRASI

Skenario 1: Setup Web Server

Skenario 2: Setup User & SSH

Skenario 3: Monitoring & Troubleshooting

Checklist Harian Administrator

SELAMAT!

JARINGAN SOSIAL

BANTUAN