1. View server time
date
2. View the current server scheduled tasks
crontab -l
3. View system configuration files (environment variables)
view /etc/profile
4. View the local IP
ifconfig or ip addr
5. View the encoding format of the current service
$LANG
6. Modify the system default encoding - command line mode
LANG="zh_CN.UTF-8" or LANG="en_US.UFT-8"
7. View the encoding format supported by the current server
locale -a
8. View the number of CPU cores
cat /proc/cpuinfo | grep ‘process’ | sort | uniq | wc -l
9. View the total memory size
cat /proc/meminfo | grep “MemTotal” | awk ‘{print $2/1024/1024}’
（注意：理论上单位换算时是除以 1024的，但实际使用的时候都是按照 1000 来算的，换算之后对齐取整数即可）
10. Check the hard disk size
