View Kernel version
Uname-r
Uname-a
To view the current Linux system version:
Cat/etc/redhat-release
To view the size of a directory
Du/home-sh
#env View Environment variables
#lsmod View kernel-loaded service modules
#du-sh usr to view the size of the specified directory
#uptime View System uptime, number of users, load
[Email protected]/]# uptime
17:42:08 up, 6:47, 1 user, load average:0.01, 0.02, 0.05
Internet
IFCONFIG-A View all network interface properties
Iptables-l View firewall rules (before CENTOS7)
Firewall-cmd--list-all View firewall settings (CENTOS7)
Route-n Viewing the routing table
NETSTAT-LNTP View all monitored ports
NETSTAT-ANTP View all established connections
Netstat-s Viewing network statistics
User:
W View Active Users
ID < user name > View information such as specified user information uid,gid,groups
Last View user logon log
Cut-d:-F1/ETC/PASSWD View all users of the system
Cut-d:-f1/etc/group View System all groups
Crontab-l checking the current user's scheduled tasks
Service:
Chkconfig--list
Chkconfig--lies |grep xx (before CENTOS7)
Systemctl list-units--type=service Service Information Simple list
Systemctl status XX
Systemctl Status |grep XX
Service XX Status
To view the current RunLevel:
Who-rh
RunLevel
The system information that can be viewed in the/proc directory is:
Cpuinfo
Filesystems File System Information
DMA Host DMA Channel information
Interrupts host interrupt Information
Ioprots host I/O port information
Meminfo Memory Information
Ersion Linux Memory version information
Linux system software information cores, systems, directories, firewalls, etc.