Essential Port Numbers for DevOps Engineers

Common Protocols and Services

1. HTTP:

   • Port: 80

   • Purpose: Unsecured web traffic.

2. HTTPS:

   • Port: 443

   • Purpose: Secure web traffic (TLS/SSL).

3. SSH:

   • Port: 22

   • Purpose: Secure shell access for remote administration.

4. FTP:

   • Port: 20 (data transfer), 21 (control)

   • Purpose: File Transfer Protocol.

5. SFTP:

   • Port: 22

   • Purpose: Secure FTP via SSH.

6. Telnet:

   • Port: 23

   • Purpose: Unsecured remote administration (rarely used now).

7. DNS:

   • Port: 53

   • Purpose: Domain Name System resolution.

8. SMTP:

   • Port: 25, 587 (with encryption), 465 (deprecated)

   • Purpose: Email sending.

9. IMAP:

   • Port: 143 (unencrypted), 993 (encrypted)

   • Purpose: Retrieve emails (modern email clients).

10. POP3:

    • Port: 110 (unencrypted), 995 (encrypted)

    • Purpose: Retrieve emails (older protocol).

DevOps and Automation Tools

1. Jenkins:

   • Port: 8080 (default)

   • Purpose: Continuous Integration/Delivery.

2. Docker:

   • Port: 2375 (unencrypted), 2376 (encrypted)

   • Purpose: Docker API.

3. Kubernetes API Server:

   • Port: 6443

   • Purpose: Communication with Kubernetes API.

4. Terraform Enterprise:

   • Port: 8800 (default)

   • Purpose: Backend services.

Databases

1. MySQL:

   • Port: 3306

   • Purpose: MySQL database.

2. PostgreSQL:

   • Port: 5432

   • Purpose: PostgreSQL database.

3. MongoDB:

   • Port: 27017

   • Purpose: MongoDB NoSQL database.

4. Redis:

   • Port: 6379

   • Purpose: In-memory data store.

5. Elasticsearch:

   • Port: 9200 (HTTP), 9300 (Node communication)

   • Purpose: Search and analytics engine.

Cloud and Monitoring Tools

1. Prometheus:

   • Port: 9090

   • Purpose: Monitoring and alerting.

2. Grafana:

   • Port: 3000

   • Purpose: Data visualization and dashboards.

3. Consul:

   • Port: 8500 (HTTP API), 8600 (DNS queries)

   • Purpose: Service discovery and configuration.

4. Vault:

   • Port: 8200

   • Purpose: Secrets management.

5. Zabbix:

   • Port: 10051 (server), 10050 (agent)

   • Purpose: Monitoring.

Version Control

1. Git (SSH):

   • Port: 22

   • Purpose: Secure Git operations.

2. Git (HTTPS):

   • Port: 443

   • Purpose: Secure Git operations via HTTPS.

Messaging and Queueing Systems

1. RabbitMQ:

   • Port: 5672 (AMQP), 15672 (Management console)

   • Purpose: Message broker.

2. Kafka:

   • Port: 9092

   • Purpose: Distributed messaging system.

Miscellaneous

1. NTP:

   • Port: 123

   • Purpose: Network Time Protocol.

2. LDAP:

   • Port: 389 (unencrypted), 636 (encrypted)

   • Purpose: Directory services.

3. SNMP:

   • Port: 161 (queries), 162 (traps)

   • Purpose: Network monitoring.

4. RDP:

   • Port: 3389

   • Purpose: Remote Desktop Protocol (Windows).

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