Network Connectivity Check

A toolkit for diagnosing network connectivity issues and verifying host/service availability.

When to Use This Skill

Activate this skill when the user needs to:

• Check if a host is reachable (ping)

• Verify if a specific port is open on a host

• Perform DNS lookups to resolve domain names

• Diagnose network connectivity problems

• Test if a service is available

Available Scripts

Always run scripts with --help first to see all available options.

Script Purpose

ping_host.py

Ping a host to check reachability

check_port.py

Check if a TCP port is open

dns_lookup.py

Perform DNS lookups

Decision Tree

Task → What do you need to check? │ ├─ Is the host reachable at all? │ └─ Use: ping_host.py <hostname> │ ├─ Is a specific service/port available? │ └─ Use: check_port.py <hostname> <port> │ └─ Need to resolve a domain name? └─ Use: dns_lookup.py <domain>

Quick Examples

Check if a host is reachable:

python scripts/ping_host.py google.com python scripts/ping_host.py 8.8.8.8 --count 5

Check if a port is open:

python scripts/check_port.py example.com 443 python scripts/check_port.py localhost 8080 --timeout 5

DNS lookup:

python scripts/dns_lookup.py example.com python scripts/dns_lookup.py example.com --type MX

Common Use Cases

• Verify web server is running: check_port.py myserver.com 80

• Test SSH access: check_port.py server.local 22

• Check database connectivity: check_port.py db.example.com 5432

• Diagnose DNS issues: dns_lookup.py problematic-domain.com

Notes

• Scripts use Python standard library only (no external dependencies)

• Ping may require appropriate permissions on some systems

• Port checks use TCP connections (not UDP)

• DNS lookups support A, AAAA, MX, TXT, NS, and CNAME record types