Quick Guide: Secure Linux Server Setup with JDK, Tomcat & Docker

Enable Security Group

Open the required ports (e.g., 80/tcp, 8080/tcp) in the cloud console, obtain the public IP address, change the root password, and reboot the instance if this is the first login.

Install BT Panel (optional GUI)

Installation

yum install -y wget && wget -O install.sh http://download.bt.cn/install/install_6.0.sh && sh install.sh

Press y to accept the default prompts.

Configure Firewall (firewalld)

# Check service status
systemctl status firewalld

# Start, restart, stop
service firewalld start
service firewalld restart
service firewalld stop

# List all rules
firewall-cmd --list-all

# Open port 80 permanently
firewall-cmd --zone=public --add-port=80/tcp --permanent
systemctl restart firewalld.service

Install JDK

Remove existing OpenJDK packages

rpm -qa | grep java
yum -y remove java-1.7.0-openjdk-1.7.0.141-2.6.10.5.el7.x86_64
yum -y remove java-1.8.0-openjdk-1.8.0.131-11.b12.el7.x86_64
# ... other versions ...

Install downloaded JDK RPM

rpm -ivh jdk-11.0.8_linux-x64_bin.rpm
java -version

Install Tomcat

tar -zxvf apache-tomcat-9.0.37.tar.gz
cd apache-tomcat-9.0.37
# Start Tomcat, e.g., ./bin/startup.sh

Install Docker CE

Prepare environment

yum -y install gcc gcc-c++

Remove previous Docker packages

yum remove docker \
    docker-client \
    docker-client-latest \
    docker-common \
    docker-latest \
    docker-latest-logrotate \
    docker-logrotate \
    docker-engine

Add Alibaba Cloud mirror repository and install Docker

yum -y install yum-utils
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
yum makecache fast
yum -y install docker-ce docker-ce-cli containerd.io

Start Docker and verify

systemctl start docker
ps -ef | grep docker