# Network Debugging Notes


DNS, WHOIS, IP addresses, ports, subnets, MAC addresses, Wi-Fi QR codes, and SSH tunnels.

This guide is the canonical guide page for related tools on ilham.dev. It should grow into practical explanations, caveats, examples, and references instead of creating one thin article per utility.

## Related tools

- [DNS Lookup](/tools/dns-lookup/) — Resolve A, AAAA, MX, TXT, NS, SOA, CAA and SRV records over DNS-over-HTTPS.
- [IP & Geolocation Lookup](/tools/ip-lookup/) — Show your public IP (or any address) with its country, city, coordinates and ISP.
- [IPv4 Address Converter](/tools/ipv4-address-converter/) — Convert between dotted, decimal, hex and binary IPv4 forms.
- [IPv4 Range Expander](/tools/ipv4-range-expander/) — Expand an IP range into the CIDR blocks that cover it.
- [IPv4 Subnet Calculator](/tools/ipv4-subnet-calculator/) — Work out the network, broadcast, mask and host range for a CIDR block.
- [IPv6 Expander](/tools/ipv6-expander/) — Expand, compress and classify an IPv6 address, with prefix and embedded IPv4 support.
- [IPv6 ULA Generator](/tools/ipv6-ula-generator/) — Generate a random IPv6 unique local address prefix.
- [MAC Address Generator](/tools/mac-address-generator/) — Generate random MAC addresses, with optional prefix.
- [MAC Address Lookup](/tools/mac-address-lookup/) — Look up the vendor behind a MAC address OUI.
- [Network Info](/tools/network-info/) — Show what this browser exposes about its connection, device, screen and locale.
- [Port Reference](/tools/port-reference/) — Search the common TCP and UDP ports with their service names and a short description.
- [Random Port Generator](/tools/random-port-generator/) — Pick one or more unused-looking port numbers.
- [SSH Tunnel Builder](/tools/ssh-tunnel-builder/) — Assemble an ssh -L, -R or -D tunnel with the right ports, identity file and keepalive options, then copy the command.
- [WHOIS Lookup](/tools/whois-lookup/) — Show registrar, registration and expiry dates, status and nameservers for a domain.
- [Wi-Fi QR Code](/tools/wifi-qr-generator/) — Build a QR code that joins a Wi-Fi network.

## Notes for future edits

- Keep the guide reusable and factual.
- Link to personal posts only when there is a real incident, measurement, migration, or lesson.
- For sensitive inputs, mention whether the related tool runs locally in the browser and warn against pasting production secrets without understanding the trust boundary.