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Use when working with IPs, ports, firewall rules, routing, or diagnosing network connectivity issues
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Based on SOC occupation classification
Use before any DevOps build, change, or new feature — refine requirements through dialogue before touching infrastructure or code
Use when working with Docker — building images, writing Dockerfiles, debugging container issues
Use to execute a written implementation plan via subagents with review checkpoints
Use when implementation is complete, all tests pass, and you need to decide how to integrate the work - guides completion of development work by presenting structured options for merge, PR, or cleanup
Use when working with Kubernetes or Helm — authoring, reviewing, hardening, or debugging manifests, Deployments, Services, Ingress, RBAC, NetworkPolicy, or cluster operations
Use when receiving code review feedback, before implementing suggestions, especially if feedback seems unclear or technically questionable - requires technical rigor and verification, not performative agreement or blind implementation
| name | network-operations |
| description | Use when working with IPs, ports, firewall rules, routing, or diagnosing network connectivity issues |
# Is the port open and listening?
ss -tlnp | grep <port>
netstat -tlnp | grep <port>
# Can you reach the host?
ping <host>
traceroute <host>
# Is the port reachable?
telnet <host> <port>
nc -zv <host> <port>
curl -v http://<host>:<port>/health
# DNS resolution
dig <hostname>
nslookup <hostname>
host <hostname>
# What's using a port?
lsof -i :<port>
fuser <port>/tcp
# ufw (Ubuntu)
ufw status verbose
ufw allow 443/tcp
ufw deny 22/tcp
ufw reload
# firewalld (CentOS/RHEL)
firewall-cmd --list-all
firewall-cmd --add-port=443/tcp --permanent
firewall-cmd --reload
# iptables (direct)
iptables -L -n -v
iptables -A INPUT -p tcp --dport 443 -j ACCEPT
AWS:
# List security group rules
aws ec2 describe-security-groups --group-ids sg-xxxxxxxx
# Add inbound rule
aws ec2 authorize-security-group-ingress \
--group-id sg-xxxxxxxx \
--protocol tcp --port 443 --cidr 0.0.0.0/0
GCP:
gcloud compute firewall-rules list
gcloud compute firewall-rules create allow-https \
--allow tcp:443 --source-ranges 0.0.0.0/0
| Symptom | Diagnosis |
|---|---|
| Connection refused | Service not running or wrong port |
| Connection timed out | Firewall blocking, wrong IP, routing issue |
| No route to host | Routing table, VPC/subnet misconfiguration |
| Intermittent drops | MTU mismatch, packet loss — run mtr |
| DNS not resolving | DNS server unreachable, wrong search domain |
ip addr show # list interfaces and IPs
ip route show # routing table
ip route add 10.0.0.0/8 via <gateway> # add route
# For Kubernetes pod networking
kubectl get pods -o wide # pod IPs
kubectl get svc # service IPs and ports
kubectl get networkpolicy # network policies