Solve the problem that the Aliyun linux server cannot be accessed after the tomcat service is built (the firewall is closed)

I set up a tomcat service today, and encountered a very strange problem. I have turned off the firewall of the service, but I can’t access the tomcat service. Baidu has been talking about firewall problems for a long time, and finally my inspiration flashed. , It turns out that the port 8080 was not opened when the security group was configured in the Alibaba Cloud background, which resulted in the tomcat not being accessible. Later, the port 8080 in the inbound direction was configured in the security group to access

1. Find the security group

2. Configure the inbound rule