4.10.1 DNS, IP addresses & ports
Every entry filed under DNS, IP addresses & ports and its subtopics.
Level
- Beginner 8 (selected, select to remove)
- Intermediate 0
- Advanced 0
What kind of help
What do these mean?
- Beginner
- You are new to this topic.
- Intermediate
- You use it, and want to get better.
- Advanced
- You know it well and need the details.
- Guided project
- Build something small from start to finish, step by step.
- Explains an idea
- Plain words on how something works and why.
- Step by step
- Numbered steps to get one task done.
- Cheat sheet
- Commands and options in a table, to look up fast.
- Fixes an error
- An error message, what it means, and how to solve it.
2 entries match these filters
- 0347 Port check script: test a list of host:port pairs with timeouts A bash script that tries a TCP connection to each host:port you give it, waits a few seconds at most, and reports… Beginner · Cheat sheet · Linux, macOS Script DNS, IP addresses & ports · Firewalls 15 Oct 2026
- 0348 DNS check script: compare answers from several resolvers A bash script that looks up one or more names against your system resolver and three public resolvers, shows each answer with… Beginner · Cheat sheet · Linux, macOS Script DNS, IP addresses & ports 15 Oct 2026