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How to analyze the similarities and differences between CentOS6 and CentOS7, I believe that many inexperienced people do not know what to do. Therefore, this paper summarizes the causes and solutions of the problem. Through this article, I hope you can solve this problem.

After introducing CentOS7, we began to understand what is the difference between 6 and 7. After we are familiar with the CentOS6 system, we will not use 7? Actually, it's not difficult. Next, let's introduce the differences between the two systems.

Init technology 2 does not have the multi-user mode of the network-> serial, which may be jammed. The init that starts the slow process as 1 is cs6upstart technology. CentOS6 uses Upstart technology instead of INIT to boot, but in order to simplify the administrator's operation, the operation habit is still the same as INIT. As a transitional technology, So,Upstart technology has been eliminated because its competitors are too strong. Representative system: CentOS6,Ubuntu14, using systemdSystemd technology from CentOS7,Ubuntu15 (RedHat7,CentOS7,Ubuntu15, etc.); the design goal is to overcome the inherent shortcomings of INIT and improve the startup speed of the system; be compatible with INIT and reduce migration costs; the main advantages: start processes with Pid 1 in parallel

[root@centos7~] # ps-ef | head-2 UID PID PPID C STIME TTY TIME CMD root10011:13? 00VOUR 01GRAM usrUniverse switched-root--system--deserialize LIBSCUBLE systemdSystemDMAE-URS 21

Pid 1 is the systemB task that starts only when Task A starts. System forgery allows two systems to start at the same time to virtualize, upgrade the kernel, boot 1024cobbler management interface supplement installation package yum-y install free nmap lrzsz dos2unix telnet screen vim lsof add software CentOS6 and CentOS7 during installation similarities and differences 1: network card name eth0 and enp5s0 traditional Linux network interface commands are eth0, eth2. Starting from CentOS7/RHEL7, a consistent and predictable method for naming network interfaces is introduced. Even if network devices are added or removed, the interface name remains fixed without having to re-enumerate, and broken hardware can be seamlessly replaced. But this new feature interferes with our automated operation and maintenance! Therefore, advanced technology has succumbed to us. CentOS7 modify the name of the network card to eth0 has been installed the system modified http://oldboy.blog.51cto.com/2561410/1722101 above method, only suitable for the first installation, very tedious automatic installation, direct configuration difference 2: network configuration related commands

Ip: the yum-y install iproute CentOS7 main push uses the ip command. Ifconfig: yum-y install net-tools setup: yum-y install setuptool obsolete command nmtui: replace setup command

Change the name of the network card after installation, there is no difference 3: host name and character set modify host name

Hostname CentOS7 / etc/hostname hostnamectl set-hostname CentOS7

Modify character set

LANG=zh_CN.UTF-8 / etc/locale.conf localectl set-locale.UTF-8

Difference 4: compatible / etc/rc.localPlease note that you must run 'chmod + x / etc/rc.d/rc.local' to ensure that this script will be executed during boot.

[root@lewen ~] # systemctl get-default multi-user.target

Difference 5: management services

Systemct: integrate the functions of service and chkconfig. Systemctl start crond.service starts the service. Systemctl stop crond.service is out of service. Systemctl restart crond.service restarts the service. Systemctl reload crond.service. Reload the service. Systemctl status crond.service views the running status of the service. Systemctl list-unit-files views all boot services. The systemctl enable crond.service boots automatically. The systemctl disable crond.service does not boot. Systemctl is-enabled crond.service checks to see if it boots on. After reading the above, have you mastered how to analyze the similarities and differences between CentOS6 and CentOS7? If you want to learn more skills or want to know more about it, you are welcome to follow the industry information channel, thank you for reading!

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