System Info — Hardware, OS, and resource information
date
System Info
Display or set the system date and time
Syntax
date [OPTIONS] [+FORMAT]
Examples
date date +"%Y-%m-%d" date +"%H:%M:%S"
df
System Info
Report disk space usage of filesystems
Syntax
df [OPTIONS] [FILE...]
Examples
df -h df -h / df -T
Common Flags
-h human-readable sizes
-T show filesystem type
-i show inode info instead
free
System Info
Display amount of free and used memory
Syntax
free [OPTIONS]
Examples
free -h free -m
Common Flags
-h human-readable
-m display in megabytes
-g display in gigabytes
-s N repeat every N seconds
hostname
System Info
Show or set the system hostname
Syntax
hostname [OPTIONS] [NAME]
Examples
hostname hostname -I hostname -f
Common Flags
-I all IP addresses
-f FQDN (fully qualified domain name)
lsblk
System Info
List information about block devices
Syntax
lsblk [OPTIONS]
Examples
lsblk lsblk -f
Common Flags
-f show filesystem info
-o specify output columns
lscpu
System Info
Display information about the CPU architecture
Syntax
lscpu
Examples
lscpu
uname
System Info
Print system information
Syntax
uname [OPTIONS]
Examples
uname -a uname -r uname -m
Common Flags
-a all information
-r kernel release
-m machine hardware name
-n hostname
uptime
System Info
Show how long the system has been running
Syntax
uptime
Examples
uptime
Notes
Shows current time, uptime duration, number of logged-in users, and load averages.