␡
- Starting Up the Terminal
- Getting Started
- Building Pipelines
- Running Commands as Superuser
- Finding Help
- Moving around the Filesystem
- Manipulating Files and Folders
- System Information Commands
- Searching and Editing Text Files
- Dealing with Users and Groups
- Getting Help on the Command Line
- Searching for Man Files
- Using Wildcards
- Executing Multiple Commands
- Moving to More Advanced Uses of the Command Line
This chapter is from the book
System Information Commands
System information commands include the following.
-
df:
Thedf
command displays filesystem disk space usage for all partitions. The commanddf-h
is probably the most useful. It uses megabytes (M
) and gigabytes (G
) instead of blocks to report. (-h
means “human-readable.”) -
free
: Thefree
command displays the amount of free and used memory in the system. For example,free -m
gives the information using megabytes, which is probably most useful for current computers. -
top
: Thetop
command displays information on your Linux system, running processes, and system resources, including the CPU, RAM, swap usage, and total number of tasks being run. To exittop
, press Q. -
uname -a
: Theuname
command with the-a
option prints all system information, including machine name, kernel name, version, and a few other details. This command is most useful for checking which kernel you’re using. -
lsb_release -a
: Thelsb_release
command with the-a
option prints version information for the Linux release you’re running. For example:
username@computer:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 12.04
Release: 12.04
Codename: precise
ifconfig
: This reports on your system’s network interfaces.iwconfig:
The iwconfig
command shows you any wireless network adapters and the wireless-specific information from them, such as speed and network connected.ps
: The ps
command allows you to view all the processes running on the machine.The following commands list the hardware on your computer, either of a specific type or with a specific method. They are most useful for debugging when a piece of hardware does not function correctly.
-
lspci
: Thelspci
command lists all PCI buses and devices connected to them. This commonly includes network cards and sound cards. -
lsusb
: Thelsusb
command lists all USB buses and any connected USB devices, such as printers and thumb drives. -
lshal:
Thelshal
command lists all devices the hardware abstraction layer (HAL) knows about, which should be most hardware on your system.