前提條件：

確保ubuntu伺服器上 已經安裝 java 8 或更高版本，安裝java8可以參考我的另一篇博文 通過 ppa 在ubuntu server 上安裝java 8

java -version

java version "1.8.0_191"
Java(TM) SE Runtime Environment (build 1.8.0_191-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.191-b12, mixed mode)

第一步：下載安裝包，解壓縮

cd /usr/local

sudo wget
 
 http://www-us.apache.org/dist/tomcat/tomcat-9/v9.0.12/bin/apache-tomcat-9.0.12.tar.gz

sudo tar xzf apache-tomcat-9.0.12.tar.gz

sudo mv apache-tomcat-9.0.12 apache-tomcat9

第二步：配置環境變數

echo "export CATALINA_HOME="/usr/local/apache-tomcat9"" >> ~/.bashrc
echo "export JAVA_HOME="/usr/lib/jvm/java-8-oracle""
 
 >> ~/.bashrc
echo "export JRE_HOME="/usr/lib/jvm/java-8-oracle/jre"" >> ~/.bashrc
source ~/.bashrc

第三步：設定使用者賬號

編輯conf/tomcat-users.xml 在 <tomcat-users> </tomcat-users> 標籤之間新增以下管理賬號.

<!-- user manager can access only manager section -->
<role rolename="manager-gui"
 
 />
<user username="manager" password="_SECRET_PASSWORD_" roles="manager-gui" />

<!-- user admin can access manager and admin section both -->
<role rolename="admin-gui" />
<user username="admin" password="_SECRET_PASSWORD_" roles="manager-gui,admin-gui" />

第四步：允許遠端IP訪問tomcat 主機已經管理tomcat

tomcat預設自允許localhost 訪問&管理tomcat伺服器，修改以下兩個檔案中允許訪問主機的IP地址的正則表示式

Manager File: ./webapps/manager/META-INF/context.xml
Host Manager File: ./webapps/host-manager/META-INF/context.xml

第五步：啟動tomcat

cd /usr/local/apache-tomcat9
chmod +x ./bin/startup.sh
./bin/startup.sh

Using CATALINA_BASE: /usr/local/apache-tomcat9
Using CATALINA_HOME: /usr/local/apache-tomcat9
Using CATALINA_TMPDIR: /usr/local/apache-tomcat9/temp
Using JRE_HOME: /usr/lib/jvm/java-8-oracle/jre
Using CLASSPATH: /usr/local/apache-tomcat9/bin/bootstrap.jar:/usr/local/apache-tomcat9/bin/tomcat-juli.jar
Tomcat started.

第六步：驗證啟動成功

開啟瀏覽器，訪問網站，如果介面顯示正常則啟動成功。

參考文件

https://tecadmin.net/install-tomcat-9-on-ubuntu/