CentOS 7.0的正式发布有不小的变动，比如不在内置net-tools，移除了service改用systemctl…以及Grub引导

 

 

修改主机名

 

#查看当前主机名#

[root@localhost ~]# hostname

localhost.localdomain

 

#修改主机名#

[root@localhost ~]# cat /etc/hostname 

#new hostname#

ipython.me

 

#重载环境#

[root@localhost ~]# su -

Last login: Sun Jul 13 14:54:08 EDT 2014 on pts/0

[root@ipython ~]# 

 

 

systemd

 

systemctl是systemd服务管理工具最主要的工具，它结合了service和chkconfig功能

##列出服务##

[root@ipython ~]# systemctl 

....

UNIT                        LOAD   ACTIVE SUB       DESCRIPTION

proc-sys...t_misc.automount loaded active waiting   Arbitrary Executable File Fo

dev-mqueue.mount            loaded active mounted   POSIX Message Queue File Sys

sys-kernel-config.mount     loaded active mounted   Configuration File System

sys-kernel-debug.mount      loaded active mounted   Debug File System

....

 

#以前常用service操作#

[root@ipython ~]# systemctl start postfix.service

[root@ipython ~]# systemctl stop postfix.service

[root@ipython ~]# systemctl restart postfix.service

[root@ipython ~]# systemctl status postfix.service

postfix.service - Postfix Mail Transport Agent

   Loaded: loaded (/usr/lib/systemd/system/postfix.service; enabled)

   Active: active (running) since Sun 2014-07-13 14:58:34 EDT; 32s ago

   ....

 

#以前chkconfig off|on#

[root@ipython ~]# systemctl enable postfix.service

[root@ipython ~]# systemctl disable postfix.service

 

#查看服务是否自启#

[root@ipython ~]# systemctl is-enabled postfix.service

disabled

 

#服务运行级别#

#init 3#

[root@ipython ~]# systemctl isolate multi-user.target

[root@ipython ~]# systemctl isolate runlevel3.target

 

#init 5#

[root@ipython ~]# systemctl isolate graphical.target

[root@ipython ~]# systemctl isolate runlevel5.target

 

##centos7 不再使用inittab文件来控制运行级别，但该文件仍然存在，并提供了索引##

# 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 /etc/systemd/system/default.target

#