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WWW Port 80 failure 1x weight measured

HTTP port 80 is not accepting connections

Failed to connect to server, is port 80 open?
Events
3,620
Pts per check
1.4
Pts missed
5,027.8
Teams hit
13/13

Authority mappings

Which work roles, knowledge units, and EWU courses this error pattern touches. Hover for context, click to drill in.

DCWF roles: CS-462 Control Systems Security Specialist CS-521 Cyber Defense Infrastructure Support Specialist CS-622 Secure Software Assessor IT-411 Technical Support Specialist IT-451 System Administrator SE-461 Systems Security Analyst
Knowledge Units: CD-ISC IT Systems Components CD-NDF Network Defense CD-OSA Operating Systems Administration CD-WAS Web Application Security
EWU courses: CSCD240-S26 CSCD210 CSCD212 CSCD240 CSCD327 CSCD379 CSCD380 CSCD434 CSCD496

What the message means

The scoring engine tried `curl http://<router>/` and got a connection refusal or timeout. The check is a simple TCP handshake + HTTP response. no content match. So if Apache is up and port 80 reaches it, this passes.

Why the service is down

Commands in order

  1. 1. 1. Apache up?
    systemctl status apache2
    Expect
    active (running)
    Interpret and next
    If inactive: `systemctl start apache2`; read `journalctl -u apache2 -n 30` if start fails.
  2. 2. 2. Listening on 80?
    ss -tlnp | grep :80
    Expect
    apache listening on 0.0.0.0:80 or *:80
    Interpret and next
    If only localhost: fix `Listen 80` in ports.conf to not bind a specific IP.
  3. 3. 3. Local curl works?
    curl -I http://localhost
    Expect
    HTTP/1.1 200 OK (or 301/302. anything that's a real response)
    Interpret and next
    If curl fails locally but Apache seems up: check apache error log, or firewall on loopback.
  4. 4. 4. Router NAT?
    /ip firewall nat print where dst-port=80
    Expect
    dstnat TCP 80 -> <server-IP>:80
    Interpret and next
    If missing, add it.
  5. 5. 5. Host iptables blocking?
    iptables -L INPUT -n -v | grep -E ':80|dpt:80'
    Expect
    No DROP/REJECT rule, or an ACCEPT rule
    Interpret and next
    If blocked: `iptables -I INPUT -p tcp --dport 80 -j ACCEPT` (save with iptables-save if persistent).

Decision tree

Answer each question to route to the right fix.

Q: curl -I http://localhost returns a response?
Yes: Problem is router/firewall. check NAT and iptables.
No:
Q: Is Apache process running?
Yes: Config problem. ports.conf or VirtualHost binding.
No: Start Apache; diagnose startup via journalctl.

External references

Other patterns on this service