Port 9000 PHP-FPM / SonarQube / Portainer · TCP

What runs on port 9000

A crowded port: PHP-FPM's FastCGI listener (which must only be reachable by the web server), SonarQube's UI, Portainer (9000/9443), MinIO's API, ClickHouse's native protocol, Prometheus' php-fpm exporter examples, and Hadoop's NameNode in older versions. PHP-FPM on TCP 9000 exposed to other hosts allows arbitrary PHP execution; use a Unix socket.

Software that uses it: PHP-FPM · SonarQube · Portainer · MinIO · ClickHouse (native) · Play Framework (dev)

Should port 9000 be open?

Loopback or the host's own network only. The service should listen on 127.0.0.1 (or a Unix socket) and be reached by a reverse proxy or by the application on the same host. If it answers on a public address, that is a misconfiguration.

• PHP-FPM: listen = /run/php/php-fpm.sock instead of 127.0.0.1:9000, and nginx fastcgi_pass unix:…
• If 9000 is open on a server you did not configure, assume PHP-FPM or ClickHouse and check which before anything else.

Check port 9000

# on the host: is anything listening, and which process?
ss -ltnp 'sport = :9000'
sudo lsof -i :9000

# from another machine: is it reachable?
nc -zv host 9000
nmap -p 9000 host
curl -v telnet://host:9000      # raw TCP connect test, Ctrl-C to leave

A port that answers from the internet when it should not is the finding; nmap from a machine outside your network (or a VPS) is the honest test, because scans from inside the LAN pass the firewall you are trying to verify.

Allow or block port 9000

# ufw (Ubuntu/Debian)
sudo ufw allow from 10.0.0.0/8 to any port 9000 proto tcp
sudo ufw deny 9000/tcp

# nftables
nft add rule inet filter input ip saddr 10.0.0.0/8 tcp dport 9000 accept
nft add rule inet filter input tcp dport 9000 drop

# iptables (legacy)
iptables -A INPUT -p tcp --dport 9000 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 9000 -j DROP

# firewalld
sudo firewall-cmd --permanent --add-rich-rule='rule family=ipv4 source address=10.0.0.0/8 port port=9000 protocol=tcp accept'

Replace 10.0.0.0/8 with the networks that need access. Allowing by source address is the rule that matters; "allow 9000" with no source is just "open".

Putting it behind nginx

server {
    listen 443 ssl;
    server_name app.example.com;
    location / {
        proxy_pass http://127.0.0.1:9000;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto https;
    }
}

Then make the application listen on 127.0.0.1:9000 only. Test which location block a request hits with the nginx location tester.

Related ports

• 9443 Portainer / HTTPS alt
• 8123 ClickHouse HTTP
• 8080 HTTP alt — Tomcat, proxies, dev servers

Part of the port number reference. Ports are 16-bit numbers; see also the subnet calculator and the packet decoder, which shows ports inside TCP and UDP headers.

Questions