add to sudoers and auto start services on Centos

贞韵1167

How to add a CentOS user to the sudoers list

vi /etc/sudoers
...## Next comes the main part: which users can run what software on## which machines (the sudoers file can be shared between multiple## systems).## Syntax:####     user    MACHINE=COMMANDS#### The COMMANDS section may have other options added to it.#### Allow root to run any commands anywhere
root    ALL=(ALL)     ALL
youruser ALL=(ALL)  ALL
How to auto start services on boot in Centos / Redhat?

To auto start a new service:

• Find out the name of service’s script from /etc/init.d/ directory e.g. mysqld or httpd
  
• Add it to chkconfig
  sudo /sbin/chkconfig --add mysqld
  
• Make sure it is in the chkconfig.
  sudo /sbin/chkconfig --list mysqld
  
• Set it to autostart
  sudo /sbin/chkconfig mysqld on
  

To stop a service from auto starting on boot

• sudo /sbin/chkconfig mysqld off
  

防火墙开放80端口

[iyunv@localhost lele]# /sbin/iptables -I INPUT -p tcp --dport 80 -j ACCEPT
[iyunv@localhost lele]# /etc/rc.d/init.d/iptables save
　　
　　
如何修改centos等linux系统的hostname？重启后也生效
简单来说，uname -a 可以看到hostname，修改步骤如下：

• uname -a 查看hostname
  
• hostname www.ctohome.com 修改下，让hostname立刻生效。
  
• vi /etc/hosts 修改原hostname为 www.ctohome.com
  
• vi  /etc/sysconfig/network 修改原hostname为 www.ctohome.com,这样可以让reboot重启后也生效
  
• reboot重启，uname -a 重新检查下。收工