System information
# uname -a # View kernel/operating system/CPU information
# cat /etc/issue # # View the operating system version
#cat /proc/version # View cpu information h # hostname # View computer name
# LSPCI -TV # List all PCI devices
# LSUSB -TV # List all USB devices
# LSMOD # List the loaded kernel module
# ENV # View environment variables
Resource information
# df -h # Check the usage of each partition
# du -sh
# grep MemTotal /proc/meminfo # Check the total amount of memory
# grep MemFree /proc/meminfo # Check the amount of free memory
# uptime # Check the system running time, number of users, load
# cat /proc/loadavg # Check the system load
disk information
# fdisk -l # View all partitions
# swapon -s # View all swap partitions
# hdparm -i /dev/hda # View disk parameters (only applicable to IDE device)
# dmesg | grep IDE # Check the IDE device detection status at startup
Network information
# iptables -L # Check the firewall settings
# route -n # Check the routing table
# netstat -lntp # View all listening ports
# netstat -antp # View all established connections
# netstat -s # View network statistics
Process information
# top # Real-time display Process status
User information
# id
# last # View user login log
# cut -d: -f1 /etc/passwd # View system All users
# cut -d: -f1 /etc/group # View all groups in the system
# crontab -l # View the current user’s scheduled tasks