树莓派3b+安装ubuntu18.04 server

1.先下载Ubuntu server

http://cdimage.ubuntu.com/ubuntu/releases/18.04.3/release/ubuntu-18.04.3-preinstalled-server-arm64+raspi3.img.xz

2.下载写入工具

win32diskimager

3.将下载的ubuntu-18.04.3-preinstalled-server-arm64+raspi3.img.xz解压，把解压后的文件用win32diskimager写入到内存卡中

4.把内存卡插入树莓派中，上电

等待两分钟吧，点一下enter键

登录，初始账户及密码

用户名：ubuntu

密码：ubuntu

初次登陆需要修改密码

至此，Ubuntu server安装成功

5.添加root用户

输入命令sudo passwd    给root用户设置密码

输入su命令，切换至root用户

root用户不允许远程登陆，修改一下

令root 允许ssh远程登录

sudo vim /etc/ssh/sshd_config

找到PermitRootLogin without-password 修改为PermitRootLogin yes  或者直接添加PermitRootLogin yes

service ssh restart 重启ssh,即可通过Windows上的ssh工具远程连接树莓派root账户了

6.修改默认源

先备份/etc/apt/sources.list，

 cp sources.list sources.list.d1

vi /etc/apt/sources.list 

然后把sources.list里面的内容替换为

## Note, this file is written by cloud-init on first boot of an instance
## modifications made here will not survive a re-bundle.
## if you wish to make changes you can:
## a.) add 'apt_preserve_sources_list: true' to /etc/cloud/cloud.cfg
##     or do the same in user-data
## b.) add sources in /etc/apt/sources.list.d
## c.) make changes to template file /etc/cloud/templates/sources.list.tmpl

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic main restricted
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-updates main restricted
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic universe
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic universe
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-updates universe
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu 
## team, and may not be under a free licence. Please satisfy yourself as to 
## your rights to use the software. Also, please note that software in 
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-updates multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-backports main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-backports main restricted universe multiverse

deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-security main restricted
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-security main restricted
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-security universe
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-security universe
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-security multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports bionic-security multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu bionic partner
# deb-src http://archive.canonical.com/ubuntu bionic partner

执行sudo apt update

sudo apt upgrade

更新软件

7.安装mysql

参考https://blog.csdn.net/Xiaofeng7s/article/details/91125516

安装mysql后一般都是远程连接使用，但Ubuntu server上的MySQL好像不允许远程连接

，所以需要设置一下

登录进去mysql 输入指令

GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'youpassword' WITH GRANT OPTION;

退出mysql

vi /etc/mysql/my.cnf 

加入下列

bind-address=0.0.0.0

然后即可

8.安装java环境

下载64位arm版本的jdk

（关于上传文件到树莓派上

apt install lrzsz

rz   这时候会弹出对话框，选择需要上传的文件

）

把jdk上传到树莓派中，解压

tar -zxvf xx.tar.gz

修改/etc/profile，在末尾添加

 export JAVA_HOME=jdk安装位置
 export CLASSPATH=.:${JAVA_HOME}/jre/lib/rt.jar:${JAVA_HOME}/lib/dt.jar:${JAVA_HOME}/lib/tools.jar
 export PATH=$PATH:${JAVA_HOME}/bin

然后重新加载一下

source /etc/profile

如上图，成功

9.安装tomcat

上传tar 文件，并解压

进入tomcat安装目录里的conf文件夹，修改server.xml,注意红色部分

 port="80" protocol="HTTP/1.1"
               connectionTimeout="20000"
               redirectPort="8443" />

查看网络端口信息：netstat -ntpl

sudo ufw status查看防火墙状态

sudo ufw allow 80添加80端口（把3306    22  端口都加进去）

为了能让tomcat能监听80端口，所以需要以管理员身份启动，但这样会报错，因为找不到java环境位置，所以还需要配置一下

参考：https://blog.csdn.net/to_baidu/article/details/52848620

这样就可以通过ip地址直接访问到tomcat了