🔌 All the Ports You’ll Use in DevOps and Networking

If you’ve spent any time in DevOps or networking, you know that ports are everywhere. They’re like the “door numbers” on a big apartment building — every service has its own door, and traffic needs to know which one to knock on.

Whether you’re setting up Docker containers, configuring Kubernetes, or just troubleshooting why something won’t connect, ports are part of the daily grind. Let’s walk through the ones you’ll see the most.

🌟 Why Ports Matter

• They tell traffic which service to reach on a machine.
• Firewalls, load balancers, and cloud security groups all rely on port rules.
• DevOps engineers use them to expose apps, databases, and APIs.
• Networking teams use them to secure and monitor traffic.

📡 Common Ports You’ll Run Into

Here’s a quick reference list of the ports that show up in almost every DevOps and networking setup:

Service	Port(s)	Protocol	What It’s For
HTTP	80	TCP	Standard web traffic
HTTPS	443	TCP	Secure web traffic
SSH	22	TCP	Remote login to servers
FTP	21	TCP	File transfers
DNS	53	UDP/TCP	Resolving domain names
SMTP	25, 587	TCP	Sending email
IMAP	143, 993	TCP	Reading email
POP3	110, 995	TCP	Downloading email
MySQL	3306	TCP	Database connections
PostgreSQL	5432	TCP	Database connections
MongoDB	27017	TCP	NoSQL database
Redis	6379	TCP	In-memory data store
RDP	3389	TCP	Remote desktop access
Kubernetes API	6443	TCP	Cluster management
Docker Daemon	2375, 2376	TCP	Container management

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🧑‍💻 How DevOps Teams Use Ports

• Containers: Docker and Kubernetes often expose app ports like 8080 or 8443.
• CI/CD Tools: Jenkins runs on 8080 by default, GitLab and other tools have their own ports.
• Monitoring: Prometheus, Grafana, and ELK stack services each use specific ports for dashboards and APIs.
• Cloud Security: AWS, Azure, and GCP security groups are basically port managers — deciding what’s open and what’s locked down.

💡 Final Thought

Ports might look like boring numbers, but they’re the backbone of communication in DevOps and networking. Every time you connect to a server, deploy a container, or troubleshoot a cloud app, you’re dealing with ports.

So the next time you see a post about ports or IP addresses, don’t scroll past. These basics are what keep your apps talking to each other — securely and reliably.