AWS EC2 Ubuntu instance launches WildFly (Java / Jakarta EE server) but seems inaccessible via browser

I am trying to setup AWS for a JBoss WildFly 31.0.0.Final to get a demo webapp up and running. So I found this tutorial:

https://kamalmeet.com/cloud-computing/amazon-ec2-step-by-step-guide-to-setup-a-java-application/

I created a ubuntu instance, along with a keypair set to read-only and manually changed some properties for the PEM file on my local Windows 11 machine. I then connected to my Ubuntu instance with my SSH shell as AWS default user named ubuntu.

I ended up with:

(I know it might not be the smartest move to post this screenshot, but for the sake of this question, I will repeat the whole process once this gets solved...)

So, I then pretty much copy-pasted the commands listed in the tutorial, with some "minor" adjustments like apt upgrade and the installation of Java 17 + JDK 17:

sudo apt update
sudo apt upgrade

sudo apt install openjdk-17-jdk openjdk-17-jre

Here I issued java -version saying:

openjdk version "17.0.9" 2023-10-17
OpenJDK Runtime Environment (build 17.0.9+9-Ubuntu-122.04)
OpenJDK 64-Bit Server VM (build 17.0.9+9-Ubuntu-122.04, mixed mode, sharing)

Now add user and group wildfly:

sudo groupadd -r wildfly
sudo useradd -r -g wildfly -d /opt/wildfly -s /sbin/nologin wildfly

Grab the latest WildFly, unzip/untar it, put it into /opt/ and create a symlink into /opt/wildfly/ to point to the actual dir.

wget https://github.com/wildfly/wildfly/releases/download/31.0.0.Final/wildfly-31.0.0.Final.tar.gz -P /tmp
sudo tar xf /tmp/wildfly-31.0.0.Final.tar.gz -C /opt/
sudo ln -s /opt/wildfly-31.0.0.Final /opt/wildfly
sudo chown -RH wildfly: /opt/wildfly

Now create a dir where the WildFly config wildfly.conf is placed:

sudo mkdir -p /etc/wildfly

sudo cp /opt/wildfly/docs/contrib/scripts/systemd/wildfly.conf /etc/wildfly/
sudo nano /etc/wildfly/wildfly.conf

The file wildfly.conf you never needed or even noticed during development on your local machine looks like this:

# The configuration you want to run
WILDFLY_CONFIG=standalone.xml

# The mode you want to run
WILDFLY_MODE=standalone

# The address to bind to
WILDFLY_BIND=0.0.0.0

I wondered what to edit here. I left it as is, making the standalone.xml being used. Bind address: IIRC 0.0.0.0 is the broadcast address, so WildFly accepts requests from anywhere in the world (??).

Now copy the file launch.sh to the WildFly bin dir and make all *.sh scripts there executable:

sudo cp /opt/wildfly/docs/contrib/scripts/systemd/launch.sh /opt/wildfly/bin/
sudo sh -c "chmod +x /opt/wildfly/bin/*.sh"

The file launch.sh looks like this:

if [ "x$WILDFLY_HOME" = "x" ]; then
    WILDFLY_HOME="/opt/wildfly"
fi

if [[ "$1" == "domain" ]]; then
    $WILDFLY_HOME/bin/domain.sh -c $2 -b $3
else
    $WILDFLY_HOME/bin/standalone.sh -c $2 -b $3
fi

That WildFly contrib script pretty much looks for the WILDFLY_HOME env var and if it is not set, assume /opt/wildfly as home, resulting in /opt/wildfly/bin/standalone.sh being executed when launch.sh is.

Now config the launcher (note, I have absolutely basic Ubuntu knowledge). From what I read, the dir /etc/systemd/system/ in Ubuntu is a more modern approach where to manage the services and sessions (to get rid of the rather old-fashioned init.d stuff AFAI understand). So we copy another WildFly contrib script to /etc/systemd/system/:

sudo cp /opt/wildfly/docs/contrib/scripts/systemd/wildfly.service /etc/systemd/system/

The wildfly.service looks like this:

[Unit]
Description=The WildFly Application Server
After=syslog.target network.target
Before=httpd.service

[Service]
Environment=LAUNCH_JBOSS_IN_BACKGROUND=1
EnvironmentFile=-/etc/wildfly/wildfly.conf
User=wildfly
LimitNOFILE=102642
PIDFile=/run/wildfly/wildfly.pid
ExecStart=/opt/wildfly/bin/launch.sh $WILDFLY_MODE $WILDFLY_CONFIG $WILDFLY_BIND
StandardOutput=null

[Install]
WantedBy=multi-user.target

So here you can see that this service file picks up the config from /etc/wildfly/wildfly.conf and that it actually executes /opt/wildfly/bin/launch.sh (this is where other env vars come into place that haven't been set at all).

The next command seem to tell Ubuntu to reload the service config (deamons) and start + enable JBoss WildFly:

sudo systemctl daemon-reload
sudo systemctl start wildfly
sudo systemctl enable wildfly

Issuing a final sudo systemctl status wildfly gives:

ubuntu@ip-172-31-19-16:~$ sudo systemctl daemon-reload
ubuntu@ip-172-31-19-16:~$ sudo systemctl start wildfly
ubuntu@ip-172-31-19-16:~$ sudo systemctl enable wildfly
ubuntu@ip-172-31-19-16:~$ sudo systemctl status wildfly
● wildfly.service - The WildFly Application Server
     Loaded: loaded (/etc/systemd/system/wildfly.service; enabled; vendor preset: enabled)
     Active: active (running) since Mon 2024-02-05 10:19:39 UTC; 16s ago
   Main PID: 22971 (launch.sh)
      Tasks: 127 (limit: 1121)
     Memory: 386.1M
        CPU: 15.964s
     CGroup: /system.slice/wildfly.service
             ├─22971 /bin/bash /opt/wildfly/bin/launch.sh standalone standalone.xml 0.0.0.0
             ├─22972 /bin/sh /opt/wildfly/bin/standalone.sh -c standalone.xml -b 0.0.0.0
             └─23093 java "-D[Standalone]" "-Djdk.serialFilter=maxbytes=10485760;maxdepth=128;maxarray=100000;maxrefs=300000" -Xms64m -Xmx512m -XX:Metaspac>

The last command is:

sudo ufw allow 8080/tcp

It's called "Uncomplicated Firewall" and seems like it is installed on most Ubuntu and Debian systems. It obviously opens port 8080 to the outside world.

QUESTION:

Whatever I do after all this, opening a browser to the public IP given + port, I simply cannot access the WildFly I just set up:

The above error message means "The connection has timed out".

So, what am I doing wrong here? Is AWS blocking port 8080 from outside? Is using HTTP disallowed at all?