Essentials of Linux Systems

The GPL is the GNU General Public License;

The Linux operating system and the extensive software associated with it are developed and distributed under the GPL.

More than 4G installs 64 bit, otherwise installs 32 bit but will be better;

Swap partition size allocation: When the memory is less than 8G, the memory is twice times, if more than 8G can be divided into 16G. View System Information commands

# uname-a # view kernel/Os/cpu information
# head-n 1/etc/issue # view OS 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 of loaded kernel modules
# env # View environment variable Resources
# free-m # View memory usage and swap area usage
# df-h # View the usage of each partition
# du-sh < directory name > # View the size of the specified directory
# grep Memtotal/proc/meminfo # view Total Memory
# grep Memfree/proc/meminfo # View the amount of free memory
# uptime # View System uptime, number of users, load
# cat/proc/loadavg # View system load disks and partitions
# Mount | column-t # View the status of the attached partition
# fdisk-l # View all partitions
# swapon-s # View all swap partitions
# hdparm-i/dev/hda # View disk parameters (for IDE devices only)
# DMESG | grep IDE # VIEW IDE device detection network at startup
# ifconfig # View the properties of all network interfaces
# iptables-l # view firewall settings
# route-n # View the routing table
# netstat-lntp # View all listening ports
# NETSTAT-ANTP # View all established connections
# netstat-s # View the network statistics process
# ps-ef # View All Processes
# top # Real-time display of process status users
# w # View active Users
# ID < user name > # View specified user information
# Last # View user log in log
# cut-d:-f1/etc/passwd # View All users of the system
# cut-d:-f1/etc/group # View all system groups
# crontab-l # View the current user's scheduled tasks service
# chkconfig–list # list all system services
# Chkconfig–list | grep on # list all started system services
# rpm-qa # View all installed packages
# Arch # View the number of system bits
# uname-i #查看系统位数

Essentials of Linux Systems