DEV Community: Ali Reza

Clean all log file with one command

Ali Reza — Sun, 28 Jul 2024 10:17:24 +0000

Find

this command search for files in a directory hierarchy.

exec switch

This switch can execute the command for each item found.

tee

read from standard input and write to standard output and files.
now pass {} \; </dev/null to this command to remove each content from file .

find  / -type f -name "*.log" -exec tee {} \; </dev/null

List of the largest files and folders in linux

Ali Reza — Sat, 27 Jul 2024 12:23:04 +0000

To get the list of the largest files and folders, we use several commands together :

Commands:

du: The 'du' command in Linux is used to estimate file and directory space usage.
pipeline( | ): The Pipe is a command in Linux that lets you use two or more commands such that output of one command serves as input to the next.
grep: Grep is a useful command to search for matching patterns in a file.
sort: SORT command is used to sort a file, arranging the records in a particular order.
head: The 'head' command in Linux is used to display the first part of files

Now use this command together:

du -ah / | grep -v "/$" | sort -rh | head -10

Docker's Command

Ali Reza — Sun, 21 Jul 2024 05:42:15 +0000

Some important Docker commands

Build Image from a Dockerfile

docker build -t {IMAGE_NAME} .

List local images

docker images
docker image ls
docker image ls -a

Remove one or more images

docker rmi {IMAGE_NAME} {IMAGE_NAME}

remove unused images (all images)

docker images prune
docker images prune -a

Login to Docker Hub (or private repository)

docker login -u {USERNAME}

Pulling image from Docker Hub (or private repository)

docker pull {IMAGE_NAME}

Start container

docker run {IMAGE_NAME}
docker run --name {container_name} {IMAGE_NAME}
docker run -p {HOST_PORT}:{CONTAINER_PORT} --name {container_name} {IMAGE_NAME}

Stop container

docker stop {CONTAINER_NAME/CONTAINER_ID}

Remove stoped container

docker rm {CONTAINER_NAME/CONTAINER_ID}

run command in container

docker exec -it {CONTAINER_NAME/CONTAINER_ID} {COMMAND}

Fetch container logs

docker logs {CONTAINER_NAME/CONTAINER_ID}
docker logs {CONTAINER_NAME/CONTAINER_ID} -f

List of running containers

docker ps
docker ps -a

Container state

docker container states

Compose

Define and run multi-container applications with Docker.
read_more

Builds, (re)creates, starts, and attaches to containers for a service.

docker compose up
docker compose up -d

Fetch container service

docker compose logs {SERVICE_NAME}
docker compose logs {SERVICE_NAME} -f

run command in service

docker compose exec -it {SERVICE_NAME} {COMMAND}

Useful links

Docker
Docker Hub
Docker Compose
Awesome compose projects

The most used Linux commands

Ali Reza — Tue, 09 Jul 2024 09:10:09 +0000

Here are the must used Linux/Ubuntu commands :

File System Management

pwd: Print the name of the current working directory.
date: print or set the system date and time.
ls: List information about the FILEs (the current directory by default).
cd: Change the shell working directory.
touch: Update the access and modification times of each FILE to the current time.
cat: Concatenate FILE(s) to standard output.
cp: Copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY.
mv: Move SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY.
rm: Remove (unlink) the FILE(s).
mkdir: Create the DIRECTORY(ies), if they do not already exist.
rmdir: Remove the DIRECTORY(ies), if they are empty.
echo: Print each text after echo.
vi:Usefull and simple editor
chmod: Change the mode of each FILE to MODE.
chown: Change the owner and/or group of each FILE to OWNER and/or GROUP.
find: Utility for comprehensive file and directory.
grep: Search for matching patterns in a file.
dd: Copy a file, converting and formatting according to the operands.
tail: Output the last part of files
head: Output the first part of files
more: Filter for paging through text one screenful at a time.
less: Like more with many other feture.

Process Management

ps: Report a snapshot of the current processes.
kill: Send a signal to a job.
top: Display Linux processes
htop: Display Linux processes with many fetures.
free: Display amount of free and used memory in the system

Device Management

df: Show information about the file system on which each FILE resides,
du: Summarize disk usage of the set of FILEs, recursively for directories.
lsmod: Show the status of modules in the Linux Kernel.
lsblk: List block devices like hard disk and partions.
fdisk: manipulate disk partition table
mount: Mount a filesystem.
umount: Unmount filesystems.

Package Management

apt: Provides a high-level commandline interface for the package management system.
apt-get update: Update package lists.
apt-get install: Install new packages.
apt-get remove: Remove packages.

Archive Management

tar: Saves many files together into a single tape or disk archive.
xz: Compress or decompress .xz and .lzma files
zip: Saves many files together into a single tape or disk archive in zip format.
unzip: Un zip archive file .

Networking

ping: Send ICMP ECHO_REQUEST to network hosts
netstat: Symbolically displays the contents of various network-related data structures.
ifconfig: Used to configure / show the kernel-resident network interfaces.
ip: Show and manipulate routing, network devices, interfaces and tunnels.
iptables: Administration tool for IPv4/IPv6 packet filtering and NAT.
wget: A non-interactive network retriever.
curl: curl is a tool for transferring data from or to a server.
ssh: Program for logging into a remote machine and for executing commands on a remote machine.
scp: Copies files between hosts on a network.
ssh-keygen: OpenSSH authentication key utility.
ssh-copy-id: Script that uses ssh to log into a remote machine.
rsync: Fast and extraordinarily versatile file copying tool.

System Information

man: An interface to the on-line reference manuals
uname: Print certain system information. With no OPTION, same as -s.
whoami: Print the user name associated with the current effective user ID.
sudo: execute a command as another user
hostnamectl: Query and change the system hostname and related settings.
history: Show history of command input by user

System Management

systemctl: Control the systemd system and service manager
journalctl: Query the systemd journal
crontab: Maintain crontab files for individual users
usermod: Modify a user account.
adduser: Add user to the system.
addgroup: Add group to the system.
passwd: Change user password.
reboot: halt, poweroff, reboot may be used to halt, power-off, or reboot the machine.

Other Management

awk: Pattern scanning and processing language
ln: Make links between files
tee: Read from standard input and write to standard output and files
cut: Remove sections from each line of files
tr: Translate, squeeze, and/or delete characters from standard input, writing to standard output.
sort: Write sorted concatenation of all FILE(s) to standard output.
uniq: Filter adjacent matching lines from INPUT (or standard input), writing to OUTPUT
git: Tool for manage versioning.

These commands are for interacting with a Linux system and by using them you can do many daily tasks.
Note that some of these commands require package installation (such as the zip command).

Good luck