DevOps & Cloud
Risk: High
Port 6443 — Kubernetes API Server
Port 6443 is the default port used by `kube-apiserver` for secure communication within a Kubernetes cluster and for external `kubectl` command management.
PORT NUMBER
6443
PROTOCOL
TCP
DEFAULT PROCESS
kube-apiserver
FIREWALL TARGET
6443/tcp
Instant Terminal Fixes for Port 6443
macOS & Linux Terminal
1. Check who is listening on port 6443:
kubectl cluster-info || sudo ss -tulpn | grep 64432. Kill process occupying port 6443 (EADDRINUSE fix):
sudo systemctl restart kubelet3. UFW Firewall Allow rule:
sudo ufw allow 6443/tcpWindows PowerShell (Admin)
1. Check listening port:
Get-NetTCPConnection -LocalPort 64432. Force kill process on port 6443:
Stop-Process -Id (Get-NetTCPConnection -LocalPort 6443).OwningProcess -Force3. Docker Port Forwarding Mapping:
minikube start --apiserver-port=6443Common Error Encountered
Unable to connect to the server: dial tcp 127.0.0.1:6443: connect: connection refused
Security Advisory & Hardening
Protect this port with RBAC authorization, audit logging, and never allow anonymous authentication (`--anonymous-auth=false`).
Frequently Asked Questions
Port 6443 Questions & Answers
Common questions regarding default services, kill commands, and firewall configurations.
Port 6443 is commonly used for Kubernetes API Server. Port 6443 is the default port used by `kube-apiserver` for secure communication within a Kubernetes cluster and for external `kubectl` command management.