Networking
Guides, how-tos, and updates on Networking.
30 articles
Advanced SSH: jump hosts, tunnels, and power-user tricks
Once you know basic SSH, a whole toolbox opens up: jump hosts to reach private servers, port forwarding, SOCKS proxies, agent forwarding, and a config file that makes it all effortless. The power-user guide.
FTP vs FTPS vs SFTP: file transfer protocols explained
FTP, FTPS, and SFTP all move files — but only two are safe, and they work in completely different ways. Here's how each protocol works, active vs passive mode, the best clients per OS, and which to use.
SSH explained: secure remote access, keys, and sessions
SSH is how you securely log into and control machines anywhere in the world. Here's what it is, how password vs public-key auth really works, how to run remote commands, and the best clients for every OS.
HTTP Status Codes Explained: what 404, 500 and 503 really mean
Every status code is your server trying to tell you something. Here's a plain-English guide to the ones you'll actually meet — what they mean, whose fault they are, and what to do about each.
How to Never Get Caught by an Expired SSL Certificate
An expired TLS certificate takes your whole site offline with a scary red warning — and it's 100% preventable. Here's why certificates expire, what it costs, and how to make sure it never catches you.
How DNS Works (and What 'Propagation' Really Means)
DNS is the internet's phonebook — and one of the most common causes of outages nobody understands. Here's how a domain name becomes an IP address, in plain English, plus what 'propagation' actually is.
502 Bad Gateway: what it means and how to fix it
A 502 Bad Gateway means the server in front of your app couldn't get a valid response from the app itself. Here's what's really happening, the usual causes, and how to fix — and prevent — it.
DNS Record Types Explained: A, AAAA, CNAME, MX, TXT and more
Setting up a domain means meeting a zoo of record types — A, AAAA, CNAME, MX, TXT, NS. Here's what each one does, when to use it, and the gotchas that trip people up.
Ping, Traceroute & MTR: network troubleshooting basics
When something's slow or unreachable, three classic tools tell you whether it's you, the network, or them. Here's how ping, traceroute and MTR work — and when to reach for each.
503 Service Unavailable: what it means and how to fix it
A 503 means your server is alive but can't handle the request right now — usually overload or maintenance. Here's what's happening, how to fix it, and how to keep it from surprising your users.
504 Gateway Timeout: what it means and how to fix it
A 504 means a proxy waited for your app to respond — and gave up. It's the signature of something slow, not something dead. Here's how to find the slowness and fix it.
TCP vs UDP: the difference, explained simply
Two protocols carry almost everything on the internet. TCP is the careful courier; UDP is the fast one that doesn't look back. Here's how they differ and when each is the right choice.
IPv4 vs IPv6: what's the difference (and why IPv6 exists)?
Every device online needs an address — and we ran out of the old kind. Here's the difference between IPv4 and IPv6, why the switch is happening, and whether you need to care.
404 Not Found: what it means and how to handle it
404 is the internet's most famous error — and unlike most, it's often nobody's emergency. Here's what it means, when it's fine, when it isn't, and how to handle it well.
403 Forbidden: causes and how to fix it
A 403 means the server understood you perfectly — and is refusing anyway. Here's what causes 'Forbidden', how it differs from 401, and how to track down the fix.
401 vs 403: Unauthorized vs Forbidden
401 and 403 are the two 'you can't have this' codes — and they're constantly confused. Here's the simple rule for telling them apart, with examples.
500 Internal Server Error: what it means and how to fix it
500 is the server's way of saying 'something went wrong and I don't know how to explain it.' Here's what causes it, how to find the real error, and how to stop it recurring.
301 vs 302 Redirects: which one should you use?
Both send visitors from one URL to another — but to search engines they mean very different things. Use the wrong one and you can quietly tank your SEO. Here's the difference.
ERR_CONNECTION_REFUSED: what it means and how to fix it
Connection refused means you reached the server's door — and it slammed shut. Nothing is listening (or something is blocking). Here's how to track down which.
What is a Network Port? (and how to monitor one)
An IP address gets you to the right machine; a port gets you to the right service on it. Here's what ports are, the common ones, and why monitoring them catches outages a website check misses.
HTTP/2 vs HTTP/3: what actually changed
HTTP keeps getting faster. HTTP/2 fixed how requests share a connection; HTTP/3 changed the connection itself. Here's what's different, in plain terms, and whether you should care.
What is Latency? (and how to reduce it)
Latency is the delay between asking for something and getting it — and it shapes how fast everything online feels. Here's what it is, what causes it, and the practical ways to cut it.
Bandwidth vs Latency: what's the difference?
“I have fast internet, so why is this slow?” Because speed has two dimensions — bandwidth and latency — and they're not the same thing. Here's the difference, with a simple analogy.
What is Packet Loss? (causes, effects and fixes)
When data packets vanish in transit, calls stutter, games rubber-band and pages crawl — even on a 'fast' connection. Here's what packet loss is, what causes it, and how to track it down.
Anycast Explained: one IP, served from everywhere
Anycast is the clever routing trick behind fast CDNs and resilient DNS: one IP address answered by the nearest of many servers. Here's how it works and why it matters.
What is BGP? (and why it can break the whole internet)
BGP is the protocol that decides how traffic travels between the world's networks — the internet's routing map. When it goes wrong, large chunks of the internet go dark. Here's how it works.
What is a Reverse Proxy?
A reverse proxy is the front door to your servers — handling traffic before it ever reaches your app. Here's what it does, why nearly every serious site uses one, and how it differs from a forward proxy.
Load Balancing Explained
A load balancer spreads traffic across many servers so no single one gets overwhelmed — and quietly routes around the ones that fail. Here's how it works and why it's the backbone of scalable, reliable sites.
What is an IP Address?
An IP address is how one machine on the internet finds another — the postal address of the digital world. Here's what it is, the difference between public and private, and the two versions in use.
What is NAT? (Network Address Translation, explained)
NAT is the quiet trick that lets all your home and office devices share a single public IP address. Here's how it works, why it exists, and the headaches it sometimes causes.