The Linux society is basically okay.

1,linux Inner Shell file: cat/etc/issue or/etc/redhat-release
Ubuntu[apt-get install-y vim] Centos[yum install-y vim] [sudo yum install epel-release]update install list
2, can apt-get update, apt-get-y upgrade yum-y upgrade Yum update
3,service Start Method:sudo service docker start = =/etc/init.d Docker start = = Systemctl Docker start
4,firewall is OK. Chkconfig iptables--list |service iptables start

user:===== Cat/etc/passwd/etc/shadow/etc/group
1,useradd-d/home/jianyeruan Jianyeruan
2,passwd
3,usermod-a-G Jianyeruan root can be used without action.
4,vi/etc/sudoers
Jianyeruan all= (All) all
5,service sshd Restart
6,shutdown-r now OK after doing 6.
7
Disable root
/etc/ssh/sshd_config
Permitrootlogin No

File. permission=======================
Ugo==a rwx
CHOMD a+r ABC
chmod U=RWX,G=RX,O=RX ABC: ibid. u= User Rights, g= group permissions, o= different groups of other user rights
chmod u-x,g+w ABC: for ABC to remove user-executed permissions, increase group Write permissions
Chomd-r A+r * Recursively traversing sub-directories [-R]

8,command:
Find/-name php.ini | | Netstat-ntld | | Lsof-i tcp:80 | | Kill-9 $ (pgrep nginx) | | Ps-eo Pid,user,group,args,etime,lstart
9,autorun root User Plus
Vi/etc/rc.local
Touch/var/lock/subsys/local
sudo service php-fpm start
sudo service nginx start
10.time
How to start the cron process:/etc/init.d/crond start
Start the Cron Process Setup command: Chkconfig--add crond
Method Two:
Add cron to the startup script:
# rc-update Add Vixie-cron Default
Crontab-l #查看你的任务
crontab-e# Edit Your task
crontab-r# Delete the contents of a user's crontab
Day of the week February 2 1 o'clock dry time-sharing what to do Sunday
0 1 2 2 1 1 0
Example:
0 4 * * 0 root emerge--sync && emerge-ud World #每周日凌晨4点, update system
0 2 1 * * Root rm-f/tmp/* #每月1号凌晨2点, clean up files in/tmp
0 8 6 5 * Root mail Robin If, I want to execute a command every 2 minutes, or I want to execute commands at 6, 12, 18, and so on every day, the cycles can be set by "/" and ",":
*/2 * * * * * Root ... #每两分钟就执行 ......... .....
0 6,12,18 * * * * Root ... #每天6点, 12, 18, ...., .....-No, No.
Every two hours
0 */2 * * * echo "has a break now." >> /tmp/test.txt
Every two hours between 11 o'clock and 8 in the morning, eight in the morning.
0 23-7/2,8 * * * echo "a good Dream:)" >> /tmp/test.txt
Every month, number 4th and Monday to Sunday, three in the morning at 11.
0 4 * 1-3 command line
January 1 morning, 4.
0 4 1 1 * command line

=========firewall Config==========sudo vi/etc/sysconfig/iptables===
: INPUT ACCEPT [0:0]
: FORWARD ACCEPT [0:0]
: OUTPUT ACCEPT [0:0]
-A input-m state--state related,established-j ACCEPT
-A input-p icmp-j ACCEPT
-A input-i lo-j ACCEPT
-A input-p tcp-m state--state new-m TCP--dport 22-j ACCEPT
-A input-p tcp-m state--state new-m TCP--dport 80-j ACCEPT
-A input-p tcp-m state--state new-m TCP--dport 9000-j ACCEPT
-A input-p tcp-m state--state new-m TCP--dport 11211-j ACCEPT
-A input-p tcp-m state--state new-m TCP--dport 22999-j ACCEPT
-A input-p tcp-m state--state new-m TCP--dport 3000-j ACCEPT
-A input-p tcp-m state--state new-m TCP--dport 9696-j ACCEPT
-A input-p tcp-m state--state new-m TCP--dport 27017-j ACCEPT
-A input-j REJECT--reject-with icmp-host-prohibited
-A forward-j REJECT--reject-with icmp-host-prohibited
COMMIT
=========download============
wget ftp://ftp.ruby-lang.org/pub/ruby/ruby-1.8.7-p334.tar.gz
Tar xvf ruby-1.8.7-p334.tar.gz
CD ruby-1.8.7-p334
./configure
Make && make install

The Linux society is basically okay.