安装ubuntu系统1804(注意有live和不带live的版本，本次用不带live的版本)

注意开始默认为NAT模式

ubuntu默认以普通用户身份登陆，切换到root

ubuntu切换到root用户，使用su root命令去切换到root权限，此时会提示输入密码

，可是怎么也输不对，提示“Authentication failure”

此时有两种情况一个是密码真的错了，另一种就是刚安装好的Linux系统，没有给root设置密码

解决办法：给root 用户设置密码，输入命令: sudo passwd root，输入密码，并确认密码

重新输入命令：su root,然后输入密码，便可切换到root权限了

返回普通用户exit,或者使用命令su username

修改配置文件默认登陆为root账户登陆

修改配置文件vim /etc/ssh/sshd_config

#PermitRootLogin prohibit-password #找到此项修改如下

PermitRootLogin yes

#UseDNS no #找到此项去掉注释，修改如下

UseDNS no

修改主机名

hostnamectl set-hostname ubuntu1804

Ubantu网络配置

网卡名称：

默认ubantu的网卡名称和Centos7类似，如：ens33,ens38等

修改网卡名称为传统命名方式：(最好在装系统时就改好，在安装界面输入net.ifnames=0 biosdevname=0)

修改配置文件为下面形式

vi /etc/default/grub

GRUB_CMDLINE_LINUX="net.ifnames=0 biosdevname=0"

生效新的grub.cfg文件

grub-mkconfig -o /boot/grub/grub.cfg #Centos里面是grub2

重启reboot

官方文档

https://help.ubuntu.com/lts/serverguide/network-configuration.html.zh-CN

配置自动获取IP(注意缩进格式)

cat /etc/netplan/01-netcfg.yaml

network

version: 2

renderer: networkd

ethernets:

ens33:

dhcp4: yes

修改网卡配置文件后需执行命令生效：netplan apply

配置静态IP：

cat /etc/netplan/01-netcfg.yaml

network:

version: 2

renderer: networkd

ethernets:

eth0:

addresses:

192.168.56.64/24

10.20.156.23/24

gateway4: 192.168.56.1

nameservers:

search: [mydomain,otherdomain]

addresses: [114.114.114.114]

查看IP和gateway

ip addr

route -n

查看DNS

ls -l /etc/resolv.conf

systemd-resolve --status

同步时间

sudo apt-get update？？

Ubuntu最小化没有selinux,不用关闭

没有防火墙，验证一下

systemctl disable firewalld

systemctl disable iptables

清空防火墙规则iptables -F

iptable -vnL查看

更改为阿里云的yum源

vim /etc/apt/sources.list

deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse

sudo apt-get update更新apt源

[c:\~]$ Connecting to 192.168.247.64:22...

Connection established.

To escape to local shell, press 'Ctrl+Alt+]'.

Welcome to Ubuntu 18.04.1 LTS (GNU/Linux 4.15.0-29-generic x86_64)

System information disabled due to load higher than 2.0

234 packages can be updated.

117 updates are security updates.

通过Xshell远程链接后如下

The programs included with the Ubuntu system are free software;

the exact distribution terms for each program are described in the

individual files in /usr/share/doc/*/copyright.

Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by

applicable law.

/usr/bin/xauth: file /root/.Xauthority does not exist

root@ubuntu-torrent:~#