无法远程访问 tomcat 服务器

Question

I'm using a VM on Google Compute Engine, I chose a g1-small machine.

I installed tomcat server. The server do run, but I can't reach it on my web browser.

I also installed httpd and I can reach port 80 on my browser, but not 8080

This are my open ports:

Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       
PID/Program name    
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1180/sshd           
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      1198/master         
tcp6       0      0 :::22                   :::*                    LISTEN      1180/sshd           
tcp6       0      0 ::1:25                  :::*                    LISTEN      1198/master         
tcp6       0      0 127.0.0.1:8005          :::*                    LISTEN      11470/java          
tcp6       0      0 :::8080                 :::*                    LISTEN      11470/java          
tcp6       0      0 :::80                   :::*                    LISTEN      11319/httpd

This is my tomcat.service file:

[Unit]
Description=Tomcat 8.5 servlet container
After=network.target

[Service]
Type=forking

User=tomcat
Group=tomcat

Environment="JAVA_HOME=/usr/lib/jvm/jre"

Environment="CATALINA_BASE=/opt/tomcat/apache-tomcat-8.5.56"
Environment="CATALINA_HOME=/opt/tomcat/apache-tomcat-8.5.56"
Environment="CATALINA_PID=/opt/tomcat/apache-tomcat-8.5.56/temp/tomcat.pid"
Environment="CATALINA_OPTS=-Xms512M -Xmx1024M -server -XX:+UseParallelGC"

ExecStart=/opt/tomcat/apache-tomcat-8.5.56/bin/startup.sh
ExecStop=/opt/tomcat/apache-tomcat-8.5.56/bin/shutdown.sh

[Install]
WantedBy=multi-user.target

I already added port 8080 to firewall with the command

firewall-cmd --zone=public --permanent --add-port=8080/tcp
firewall-cmd --reload

But when I list the firewall settings I get this

trusted (active)
 target: ACCEPT
 icmp-block-inversion: no
 interfaces: eth0
 sources: 
 services: http https
 ports: 
 protocols: 
 masquerade: no
 forward-ports: 
 source-ports: 
 icmp-blocks: 
 rich rules: 

Answer 1

To solve your issue you should configure GCP Firewall to allow ingress connections to your Tomcat server.

Have a look at the documentation Configuring Firewall Rules and follow instruction Creating a firewall ingress rule via Console or via command line:

gcloud compute firewall-rules create tomcat-server-allow-ingress --direction=INGRESS --priority=1000 --network=default --action=ALLOW --rules=tcp:8080 --source-ranges=0.0.0.0/0 --target-tags=tomcat-server

I'd recommend you to replace 0.0.0.0/0 with your IPs and use network tags to apply your rule to your VM instance directly:

gcloud compute instances add-tags tomcat-server --zone=europe-west3-a --tags=tomcat-server