ubuntu的常用配置

1. 网卡设置

sudo vim /etc/network/interfaces

auto ens33
iface ens33 inet static
address 192.168.8.100
netmask 255.255.255.0
gateway 192.168.8.2
dns-nameserver 119.29.29.29
#dns-nameservers 221.130.33.52 221.130.33.60

vim /etc/resolv.conf
nameserver 192.168.10.1
#阿里的DNS：223.5.5.5

sudo /etc/init.d/networking restart

sudo vim /etc/NetworkManager/NetworkManager.conf
打开该文件，将“managed=false”修改为“managed=true”

sudo service network-manager restart

2. Ubuntu 16.04 修改为几个国内更新源

sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak
sudo vim /etc/apt/source.list

把下面的任意一下复制到source.list中去，并覆盖原来的文件内容。
中科大源
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial-security main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial-updates main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial-proposed main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial-security main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial-updates main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial-proposed main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse

东北大学源
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial main restricted #Added by software-properties
deb http://mirror.neu.edu.cn/ubuntu/ xenial main restricted
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial restricted multiverse universe #Added by software-properties
deb http://mirror.neu.edu.cn/ubuntu/ xenial-updates main restricted
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial-updates main restricted multiverse universe #Added by software-properties
deb http://mirror.neu.edu.cn/ubuntu/ xenial universe
deb http://mirror.neu.edu.cn/ubuntu/ xenial-updates universe
deb http://mirror.neu.edu.cn/ubuntu/ xenial multiverse
deb http://mirror.neu.edu.cn/ubuntu/ xenial-updates multiverse
deb http://mirror.neu.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse #Added by software-properties
deb http://archive.canonical.com/ubuntu xenial partner
deb-src http://archive.canonical.com/ubuntu xenial partner
deb http://mirror.neu.edu.cn/ubuntu/ xenial-security main restricted
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial-security main restricted multiverse universe #Added by software-properties
deb http://mirror.neu.edu.cn/ubuntu/ xenial-security universe
deb http://mirror.neu.edu.cn/ubuntu/ xenial-security multiverse

清华大学
# deb cdrom:[Ubuntu 16.04 LTS _Xenial Xerus_ - Release amd64 (20160420.1)]/ xenial main restricted
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial main restricted
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates main restricted
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial universe
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates universe
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial multiverse
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates multiverse
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security main restricted
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security universe
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security multiverse

阿里云源
# deb cdrom:[Ubuntu 16.04 LTS _Xenial Xerus_ - Release amd64 (20160420.1)]/ xenial main restricted
deb-src http://archive.ubuntu.com/ubuntu xenial main restricted #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb http://mirrors.aliyun.com/ubuntu/ xenial multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse #Added by software-properties
deb http://archive.canonical.com/ubuntu xenial partner
deb-src http://archive.canonical.com/ubuntu xenial partner
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-security universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-security multiverse

sudo apt-get update

3. Ubuntu的图形网络配置内容都配置到哪里了？

sudo cat /etc/NetworkManager/system-connections/Wired\ connection\ 2

[connection]
id=Wired connection 2
uuid=18fcdfd4-e0b5-3343-9dec-78a06270671a
type=ethernet
autoconnect-priority=-999
permissions=
secondaries=
timestamp=1540015753

[ethernet]
duplex=full
mac-address=00:0C:29:C7:A9:B9
mac-address-blacklist=

[ipv4]
address1=192.168.135.100/24
dns-search=
method=manual

[ipv6]
addr-gen-mode=stable-privacy
dns-search=
ip6-privacy=0
method=auto

总结：

1）配置 /etc/network/interfaces文件

此为Linux传统的配置方式，通过address、netmask、gateway等字段来配置。DNS信息保存在/etc/resolv.conf文件中。

2）配置/etc/NetworkManager/system-connections目录下的文件

这是配合图形界面配置程序NetworkManager，可以在桌面通过图形界面配置，配置信息保存在这个目录下的文件中。
两种配置方法只能选用一种，如果eth0同时出现在两个配置文件中，则以 /etc/network/interfaces中的配置为准。

4. 考虑到ubuntu的图形界面还是比较耗内存的，所以决定将其关闭

	1）、首先我们修改grub文件，把其中的GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"改为GRUB_CMDLINE_LINUX_DEFAULT="text"，
	还有取消GRUB_TERMINAL=console之前的注释#。
     
     $sudo vim /etc/default/grub

	2）、然后更新我们的grub。

　　$sudo update-grub

	3）、设置开机进入字符界面。

　　$sudo systemctl set-default multi-user.target

	4）、然后我们重新启动我们的ubuntu，直接就进入字符界面了。

　　$sudo reboot 

	5）、在字符界面下要登录图形界面可以使用以下的命令。

　　$sudo systemctl start lightdm

	6）、如果要回到开机启动直接进入图形界面，可以执行以下的命令。

　　$sudo systemctl set-default graphical.target

5. 修改主机名，以及解析主机名

第一步：修改主机名：

　　vim  /etc/hostname

第二步：修改网络解析名称：

　　vim /etc/hosts

第三步：重启网络配置服务(或者刷新dns)：

　　sudo /etc/init.d/networking restart（sudo /etc/init.d/dns-clean start）

6. 如何切换到root

sudo su root
passwd root
定义root的密码，之后登录普通用户就可以su root了。

再或者直接修改root的密码
sudo passwd root