Network Diagnostics Learning Hub
Network diagnostics: ping + port checker tool, 70+ port reference with security details (Zookeeper, Kafka, Steam, RTMP, Minecraft), glossary, how-to guides.
Glossary (1) all →
How-to (1) all →
Ports (78) all →
Port 28910 — Nintendo Wi-Fi Connection
TCP port 28910 — Nintendo Wi-Fi Connection / GameSpy: DS, Wii, 3DS matchmaking. Legacy-only service.
Port 47808 — BACnet/IP
UDP port 47808 (0xBAC0) — BACnet/IP: HVAC, lighting, access control in buildings.
Port 20000 — DNP3
TCP port 20000 (DNP3): protocol for power/water utilities. Secure Authentication v5, IEC 62351.
Port 502 — Modbus TCP
TCP port 502 (Modbus TCP): industrial SCADA/PLC protocol, IoT gateways. Security: no auth, must be isolated.
Port 8554 — RTSP (alternate to 554)
TCP port 8554 — RTSP: IP cameras, streaming. ONVIF, VLC, ffmpeg. Alternate to the default 554.
Port 25565 (TCP) — Minecraft Java Edition server
Port 25565 is used by Minecraft Java Edition server. Standard port for Minecraft Java. Security, how to check, best practices.
Port 2049 (TCP/UDP) — NFS (Network File System)
Port 2049 is used by NFS (Network File System). Standard port for NFS. Security, how to check, best practices.
Port 5222 (TCP) — XMPP Jabber (clients)
Port 5222 is used by XMPP Jabber (clients). Standard port for XMPP client. Security, how to check, best practices.
Port 27015 (UDP/TCP) — Steam Game Servers
Port 27015 is used by Steam Game Servers. Standard port for Steam / Source. Security, how to check, best practices.
Port 19132 (UDP) — Minecraft Bedrock Edition server
Port 19132 is used by Minecraft Bedrock Edition server. Standard port for Minecraft Bedrock. Security, how to check, best practices.
Port 7777 (TCP/UDP) — Unreal Tournament / Terraria / Ark: Survival
Port 7777 is used by Unreal Tournament / Terraria / Ark: Survival. Standard port for Unreal / Terraria / Ark. Security, how to check, best …
Port 161 (UDP) — SNMP (Network Monitoring)
Port 161 is used by SNMP (Network Monitoring). Standard port for SNMP. Security, how to check, best practices.
Port 10000 (TCP) — Webmin / VPN admin
Port 10000 is used by Webmin / VPN admin. Standard port for Webmin / BackupPC. Security, how to check, best practices.
Port 1935 (TCP) — RTMP (Flash/OBS streaming)
Port 1935 is used by RTMP (Flash/OBS streaming). Standard port for RTMP. Security, how to check, best practices.
Port 6000 (TCP) — X Window System
Port 6000 is used by X Window System. Standard port for X11. Security, how to check, best practices.
Port 11211 (TCP/UDP) — Memcached
Port 11211 is used by Memcached. Standard port for Memcached. Security, how to check, best practices.
Port 4222 (TCP) — NATS Messaging
Port 4222 is used by NATS Messaging. Standard port for NATS. Security, how to check, best practices.
Port 2375 (TCP) — Docker daemon (unsecured)
Port 2375 is used by Docker daemon (unsecured). Standard port for Docker API. Security, how to check, best practices.
Port 5900 (TCP) — VNC Remote Desktop
Port 5900 is used by VNC Remote Desktop. Standard port for VNC. Security, how to check, best practices.
Port 27018 (TCP) — MongoDB sharded cluster
Port 27018 is used by MongoDB sharded cluster. Standard port for MongoDB shard. Security, how to check, best practices.
Port 50000 (TCP) — SAP NetWeaver AS Java
Port 50000 is used by SAP NetWeaver AS Java. Standard port for SAP NetWeaver. Security, how to check, best practices.
Port 1080 (TCP) — SOCKS proxy (v4/v5)
Port 1080 is used by SOCKS proxy (v4/v5). Standard port for SOCKS Proxy. Security, how to check, best practices.
Port 3128 (TCP) — Squid HTTP proxy
Port 3128 is used by Squid HTTP proxy. Standard port for Squid Proxy. Security, how to check, best practices.
Port 9090 (TCP) — Prometheus UI + API
Port 9090 is used by Prometheus UI + API. Standard port for Prometheus. Security, how to check, best practices.
Port 2181 (TCP) — Apache Zookeeper
Port 2181 is used by Apache Zookeeper. Standard port for Zookeeper. Security, how to check, best practices.
Port 7000 (TCP) — Cassandra inter-node
Port 7000 is used by Cassandra inter-node. Standard port for Cassandra. Security, how to check, best practices.
Port 9100 (TCP) — Prometheus node_exporter
Port 9100 is used by Prometheus node_exporter. Standard port for node_exporter. Security, how to check, best practices.
Port 5000 (TCP) — Docker Registry / Flask dev
Port 5000 is used by Docker Registry / Flask dev. Standard port for Docker Registry / Flask. Security, how to check, best practices.
Port 6380 (TCP) — Redis over TLS
Port 6380 is used by Redis over TLS. Standard port for Redis TLS. Security, how to check, best practices.
Port 4369 (TCP) — Erlang Port Mapper Daemon
Port 4369 is used by Erlang Port Mapper Daemon. Standard port for EPMD (Erlang). Security, how to check, best practices.
Port 8000 (TCP) — Django runserver / MinIO
Port 8000 is used by Django runserver / MinIO. Standard port for Django / MinIO. Security, how to check, best practices.
Port 10250 (TCP) — Kubernetes kubelet API
Port 10250 is used by Kubernetes kubelet API. Standard port for kubelet. Security, how to check, best practices.
Port 8081 (TCP) — Package repos (Nexus/Artifactory)
Port 8081 is used by Package repos (Nexus/Artifactory). Standard port for JFrog / Sonatype Nexus. Security, how to check, best practices.
Port 5601 (TCP) — Kibana UI (Elastic Stack)
Port 5601 is used by Kibana UI (Elastic Stack). Standard port for Kibana. Security, how to check, best practices.
Port 9000 (TCP) — Portainer Docker UI / SonarQube
Port 9000 is used by Portainer Docker UI / SonarQube. Standard port for Portainer / SonarQube. Security, how to check, best practices.
Port 9300 (TCP) — Elasticsearch inter-node
Port 9300 is used by Elasticsearch inter-node. Standard port for Elasticsearch transport. Security, how to check, best practices.
Port 8086 (TCP) — InfluxDB time-series database
Port 8086 is used by InfluxDB time-series database. Standard port for InfluxDB. Security, how to check, best practices.
Port 3000 (TCP) — Grafana UI / Node.js dev
Port 3000 is used by Grafana UI / Node.js dev. Standard port for Grafana / Node.js dev. Security, how to check, best practices.
Port 3478 (UDP) — STUN/TURN server (WebRTC)
Port 3478 is used by STUN/TURN server (WebRTC). Standard port for STUN/TURN. Security, how to check, best practices.
Port 5984 (TCP) — Apache CouchDB
Port 5984 is used by Apache CouchDB. Standard port for CouchDB. Security, how to check, best practices.
Port 1521 (TCP) — Oracle Database listener
Port 1521 is used by Oracle Database listener. Standard port for Oracle Database. Security, how to check, best practices.
Port 9092 (TCP) — Apache Kafka broker
Port 9092 is used by Apache Kafka broker. Standard port for Kafka. Security, how to check, best practices.
Port 2379 (TCP) — etcd distributed KV store
Port 2379 is used by etcd distributed KV store. Standard port for etcd. Security, how to check, best practices.
Port 6443 (TCP) — Kubernetes API server
Port 6443 is used by Kubernetes API server. Standard port for Kubernetes API. Security, how to check, best practices.
Port 5672 (TCP) — RabbitMQ AMQP protocol
Port 5672 is used by RabbitMQ AMQP protocol. Standard port for RabbitMQ AMQP. Security, how to check, best practices.
Port 15672 (TCP) — RabbitMQ Management UI
Port 15672 is used by RabbitMQ Management UI. Standard port for RabbitMQ Management. Security, how to check, best practices.
Port 1883 (TCP) — MQTT IoT broker (plain)
Port 1883 is used by MQTT IoT broker (plain). Standard port for MQTT. Security, how to check, best practices.
Port 139 (NetBIOS-SSN) — What It Is and Security [2026]
Port 139 — NetBIOS-SSN. What it is, why it matters, vulnerabilities, check online free.
Port 389 (LDAP) — What It Is and Security [2026]
Port 389 — LDAP. What it is, why it matters, vulnerabilities, check online free.
Port 445 (SMB) — What It Is and Security [2026]
Port 445 — SMB. What it is, why it matters, vulnerabilities, check online free.
Port 554 (RTSP) — What It Is and Security [2026]
Port 554 — RTSP. What it is, why it matters, vulnerabilities, check online free.
Port 636 (LDAPS) — What It Is and Security [2026]
Port 636 — LDAPS. What it is, why it matters, vulnerabilities, check online free.
Port 1194 (OpenVPN) — What It Is and Security [2026]
Port 1194 — OpenVPN. What it is, why it matters, vulnerabilities, check online free.
Port 1433 (MSSQL) — What It Is and Security [2026]
Port 1433 — MSSQL. What it is, why it matters, vulnerabilities, check online free.
Port 1723 (PPTP) — What It Is and Security [2026]
Port 1723 — PPTP. What it is, why it matters, vulnerabilities, check online free.
Port 5060 (SIP) — What It Is and Security [2026]
Port 5060 — SIP. What it is, why it matters, vulnerabilities, check online free.
Port 9200 (Elasticsearch) — What It Is and Security [2026]
Port 9200 — Elasticsearch. What it is, why it matters, vulnerabilities, check online free.
Port 27017 (MongoDB) — What It Is and Security [2026]
Port 27017 — MongoDB. What it is, why it matters, vulnerabilities, check online free.
Port 123 (NTP) — What It Is and Security [2026]
Port 123 — NTP. What it is, why it matters, vulnerabilities, check online free.
Port 587 (SMTP submission) — What It Is and How to Check [20
Port 587 — SMTP submission. What it is, why it matters, security, how to check if it's open online.
Port 21 (FTP) — What It Is and How to Check [2026]
Port 21 — FTP. What it is, why it matters, security, how to check if it's open online.
Port 22 (SSH / SFTP) — What It Is and How to Check [2026]
Port 22 — SSH / SFTP. What it is, why it matters, security, how to check if it's open online.
Port 23 (Telnet) — What It Is and How to Check [2026]
Port 23 — Telnet. What it is, why it matters, security, how to check if it's open online.
Port 25 (SMTP) — What It Is and How to Check [2026]
Port 25 — SMTP. What it is, why it matters, security, how to check if it's open online.
Port 53 (DNS) — What It Is and How to Check [2026]
Port 53 — DNS. What it is, why it matters, security, how to check if it's open online.
Port 80 (HTTP) — What It Is and How to Check [2026]
Port 80 — HTTP. What it is, why it matters, security, how to check if it's open online.
Port 110 (POP3) — What It Is and How to Check [2026]
Port 110 — POP3. What it is, why it matters, security, how to check if it's open online.
Port 143 (IMAP) — What It Is and How to Check [2026]
Port 143 — IMAP. What it is, why it matters, security, how to check if it's open online.
Port 443 (HTTPS) — What It Is and How to Check [2026]
Port 443 — HTTPS. What it is, why it matters, security, how to check if it's open online.
Port 465 (SMTPS) — What It Is and How to Check [2026]
Port 465 — SMTPS. What it is, why it matters, security, how to check if it's open online.
Port 993 (IMAPS) — What It Is and How to Check [2026]
Port 993 — IMAPS. What it is, why it matters, security, how to check if it's open online.
Port 995 (POP3S) — What It Is and How to Check [2026]
Port 995 — POP3S. What it is, why it matters, security, how to check if it's open online.
Port 3306 (MySQL) — What It Is and How to Check [2026]
Port 3306 — MySQL. What it is, why it matters, security, how to check if it's open online.
Port 3389 (RDP) — What It Is and How to Check [2026]
Port 3389 — RDP. What it is, why it matters, security, how to check if it's open online.
Port 5432 (PostgreSQL) — What It Is and How to Check [2026]
Port 5432 — PostgreSQL. What it is, why it matters, security, how to check if it's open online.
Port 6379 (Redis) — What It Is and How to Check [2026]
Port 6379 — Redis. What it is, why it matters, security, how to check if it's open online.
Port 8080 (HTTP alternate) — What It Is and How to Check [20
Port 8080 — HTTP alternate. What it is, why it matters, security, how to check if it's open online.
Port 8443 (HTTPS alternate) — What It Is and How to Check [2
Port 8443 — HTTPS alternate. What it is, why it matters, security, how to check if it's open online.
Alternatives (2) all →
Check-Host.net Alternatives 2026 — Multi-Region Checks
Check-Host.net is a multi-region network check from 40+ nodes. Alternatives: Enterno.io, SiteCheck, WhereIsItUp, DownInspector.
Shodan Alternatives 2026 — Exposed Service Search
Shodan is the internet-exposure search. Alternatives: Enterno.io Port Scanner, Censys, ZoomEye, BinaryEdge.