General Linux Commands | In terminal

Check operating system
cat/etc/*rel*

Check system info
- CPU
  - cat /proc/cpuinfo
- Memory
  - cat /proc/meminfo

ports - Check for listening ports.
netstat -tulpn
Check users and passwords (PUID and)
getent passwd
change ownership of directory/folder or file
- directory / folder
  - chown root:root filename/
  - chown -R root:root filename/ (all sub folders/files)
- files
  - chmod 775 filename/

Check file size and other info: Different ways to check for files size

ls -lh
- ls -l filename #check size of the specified file (bytes)
- ls -l * #check size of all the files in the current directory
```
apt-get update
```
- ls -al * #check size of all the files including hidden files in the current directory
- ls -al dir/ #check size of all the files including hidden files in the ‘dir’ directory
- du -sh filename
- du -sh -- * Shows disk space usage
- df -h . Shows free disk space

Show block devises | show drives

lsblk

Show drive serial numbers

lsblk --nodeps -o name,serial

Minimize: Go back to terminal without getting out of your doc

Ctrl=Z
To go back to the doc fg Press enter

Copy File from Host to Container

docker cp doc.txt container_id:/doc.txt
Copy host-file-name container_id:/new-file-name.txt

Run docker-compose from another directory

docker-compose -f /tmp/myproject/docker-compose.yml up -d

Updating:

Debian:

update the package index files in Linux to get the latest list of available packages in the repositories.

apt-get update

upgrade currently installed software packages to their latest versions. Under no circumstances are existing packages removed:

apt-get upgrade

enhanced version of the apt-upgrade command. Apart from upgrading existing software packages, it installs and removes some packages to satisfy some dependencies.

apt-get

Computer susbend / wakeup automatically

sudo rtcwake -m [type of suspend] -s [number of seconds]
sudo rtcwake -m 5 -s 30

Disk shutoff for 60 seconds

sudo rtcwake -m disk -s 60

Disk shutoff and turn on later

sudo rtcwake -m no -l -t $(date +%s -d 'tomorrow 09:00')

Types of Suspend

The -m switch accepts the following types of suspend:

standby – Standby offers little power savings, but restoring to a running system is very quick. This is the default mode if you omit the -m switch.

mem – Suspend to RAM. This offers significant power savings – everything is put into a low-power state, except your RAM. The contents of your memory are preserved.

disk – Suspend to disk. The contents of your memory are written to disk and your computer is powered off. The computer will turn on and its state will be restored when the timer completes.

off – Turn the computer off completely. rtcwake’s man page notes that restoring from “off” isn’t officially supported by the ACPI specification, but this works with many computers anyway.

no – Don’t suspend the computer immediately, just set the wakeup time. For example, you could tell your computer to wake up at 6am. After that, can put it to sleep manually at 11pm or 1am – either way, it will wake up at 6am.

Seconds vs. Specific Time
-s this option takes a number of seconds in the future. For example, -s 60 wakes your computer up in 60 seconds, while -s 3600 wakes your computer up in an hour.

-t this option allows you to wake your computer up at a specific time. This switch wants a number of seconds since the Unix epoch (00:00:00 UTC on January 1, 1970). To easily provide the correct number of seconds, combine the **date** command with the rtcwake command.

-l this switch tells rtcwake that the hardware clock is set to local time, while the **-u** switch tells rtcwake that the hardware clock (in your computer’s BIOS) is set to UTC time. Linux distributions often set your hardware clock to UTC time and translate that to your local time.

make a [[Cronjob]]