System
uname -a # View kernel/operating system/CPU information
cat /etc/issue # View operating system version
cat /proc/cpuinfo # View CPU information
hostname # View computer name
lspci - tv # List all PCI devices
lsusb -tv # List all USB devices
lsmod # List loaded kernel modules
env # View environment variables
resources
free -m # View memory usage and swapping Area usage
df -h # Check the usage of each partition
du -sh
grep MemTotal /proc/meminfo # Check the total memory
grep MemFree /proc /meminfo # Check the amount of free memory
uptime # Check the system running time, number of users, and load
cat /proc/loadavg # View system load
disks and partitions
mount | column -t # View attached partition status
fdisk -l # View all partitions www.2cto.com
swapon -s # View All swap partitions
hdparm -i /dev/hda # View disk parameters (only applicable to IDE devices)
dmesg | grep IDE # View the IDE device detection status at startup
Network
ifconfig # View the properties of all network interfaces
iptables -L # View firewall settings
route -n # View routing table
netstat -lntp # View all listening ports
netstat -antp # View all established connections
netstat -s # View network statistics
Process
ps -ef # View all processes
top # Display process status in real time
User
w # View active users
id
last # View user login log
cut -d: -f1 /etc/ passwd # View all users of the system
cut -d: -f1 /etc/group # View all groups of the system
crontab -l # View the current user’s scheduled tasks
services
chkconfig --list # List all system services
chkconfig --list | grep on # List all started system services
Programs
rpm -qa # View all installed software packages
Common commands are organized as follows:
Check the serial number of the motherboard: dmidecode | grep -i 'serial number'
View CPU information: cat /proc/cpuinfo or dmesg | grep -i 'cpu' or dmidecode -t processor
View memory information: cat /proc/meminfo [free -m][vmstat]
View board information: cat /proc/pci
View graphics card/sound card information: lspci |grep -i 'VGA'[dmesg | grep -i 'VGA']
View network card information: dmesg | grep -i 'eth'[cat /etc/sysconfig/hwconf | grep -i eth][lspci | grep -i 'eth']
View PCI information: lspci (more intuitive than cat /proc/pci)
View USB devices: cat /proc/bus/usb/devices
View keyboard and mouse: cat /proc/bus/input/devices
View system hard disk information and Usage: fdisk & disk – l & df
View the interrupt request (IRQ) of each device: cat /proc/interrupts
View the system architecture: uname -a