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安装完CentOS 7 minimal后，无力吐槽，变化之大，发现以前常用的一些命令都没有。
一、常用命令安装
查看anaconda-ks.cfg，原来是没装base group的包
[root@centos7 ~]# cat anaconda-ks.cfg
#version=RHEL7
# System authorization information
auth –enableshadow –passalgo=sha512
# Use CDROM installation media
cdrom
# Run the Setup Agent on first boot
firstboot –enable
ignoredisk –only-use=sda
# Keyboard layouts
keyboard –vckeymap=us –xlayouts=’us’
# System language
lang en_US.UTF-8 –addsupport=zh_CN.UTF-8
# Network information
network –bootproto=dhcp –device=eno16777736 –onboot=off –ipv6=auto
network –hostname=localhost.localdomain
# Root password
rootpw –iscrypted $6$Zz5VMf1HPPRm0YRL$QSoaU9pAUApXMj9BXuK5qlUFGAfCv9Y/ylVGUcDYv.lrxfNodTiI/7DO1UR7carvL1EdgwQpuiwDt524f6.GR.
# System timezone
timezone Asia/Chongqing –isUtc –nontp
# System bootloader configuration
bootloader –location=mbr –boot-drive=sda
autopart –type=lvm
# Partition clearing information
clearpart –none –initlabel
%packages
@core # 这里只有core
%end
[root@centos7 ~]# yum groupinstall base # 安装完后ifconfig、service、chkconfig等命令就都有了
二、运行级别切换
[root@centos7 ~]# cat /etc/inittab # 系统运行级别的设置方式也变化了
# inittab is no longer used when using systemd.
#
# ADDING CONFIGURATION HERE WILL HAVE NO EFFECT ON YOUR SYSTEM.
#
# Ctrl-Alt-Delete is handled by /etc/systemd/system/ctrl-alt-del.target
#
# systemd uses ‘targets’ instead of runlevels. By default, there are two main targets:
#
# multi-user.target: analogous to runlevel 3
# graphical.target: analogous to runlevel 5
#
# To set a default target, run:
#
# ln -sf /lib/systemd/system/<target name>.target /etc/systemd/system/default.target
这里写的很明白了，做个软链修改默认运行级别
[root@centos7 system]# ll /lib/systemd/system/runlevel*.target # 系统0-6 7个运行级别，2 3 4 运行指向同一个文件
lrwxrwxrwx 1 root root 15 Oct 11 03:51 /lib/systemd/system/runlevel0.target -> poweroff.target
lrwxrwxrwx 1 root root 13 Oct 11 03:51 /lib/systemd/system/runlevel1.target -> rescue.target
lrwxrwxrwx 1 root root 17 Oct 11 03:51 /lib/systemd/system/runlevel2.target -> multi-user.target
lrwxrwxrwx 1 root root 17 Oct 11 03:51 /lib/systemd/system/runlevel3.target -> multi-user.target
lrwxrwxrwx 1 root root 17 Oct 11 03:51 /lib/systemd/system/runlevel4.target -> multi-user.target
lrwxrwxrwx 1 root root 16 Oct 11 03:51 /lib/systemd/system/runlevel5.target -> graphical.target
lrwxrwxrwx 1 root root 13 Oct 11 03:51 /lib/systemd/system/runlevel6.target -> reboot.target
三、systemctl管理系统服务
systemctl可以看作是service和chkconfig的组合
| job |
chkconfig、service | systemctl |
| 服务开机自启动 | chkconfig –level 3 httpd on | systemctl enable httpd |
| 服务不开机自启动 | chkconfig –level 3 httpd off | systemctl disable httpd |
|
服务状态 |
service httpd status |
systemctl status httpd(服务详细信息) systemctl is-active httpd(只显示是否active)
|
| 所有服务的启动状态 | chkconfig –list | systemctl list-units –type=service |
| 启动服务 | service httpd start | systemctl start httpd |
| 停止服务 | service httpd stop | systemctl stop httpd |
| 重启服务 | service httpd restart | systemctl restart httpd |
centos 7之前的版本都采用Sysvinit的系统启动进程管理体系，因为是串行的进程启动流程，可能因为某个进程的阻塞而影响启动过程。centos 7使用systemd。目标是尽可能启动更少进程；尽可能将更多进程并行启动（这是性能优于SysVinit的理念基础）。
更详解的systemd介绍 http://www.linuxidc.com/Linux/2014-11/109232.htm
RHEL7/CentOS7默认运行级别和终端分辨率 http://www.linuxidc.com/Linux/2014-07/104759.htm
U盘安装CentOS 7.0图文详解教程 http://www.linuxidc.com/Linux/2014-10/108014.htm
U盘安装64位CentOS 6.5方法 http://www.linuxidc.com/Linux/2014-04/100035.htm
Win7安装64位CentOS 6.4双系统详细图文教程 http://www.linuxidc.com/Linux/2014-04/100032.htm
CentOS与Windows双系统安装注意事项记录 http://www.linuxidc.com/Linux/2014-05/101571.htm
UEFI+GPT安装Windows8和CentOS双系统 http://www.linuxidc.com/Linux/2014-05/101575.htm
Windows8.1和CentOS6.5双系统安装 http://www.linuxidc.com/Linux/2014-05/101581.htm
更多CentOS相关信息见CentOS 专题页面 http://www.linuxidc.com/topicnews.aspx?tid=14
本文永久更新链接地址：http://www.linuxidc.com/Linux/2014-11/109231.htm
