How servers, networks and protection really work.
Long-form guides for people who run things on the internet: what a VPS is made of, where a web request spends its time, what an attack actually exhausts. Each one has diagrams, worked examples and its sources at the end.
23 guides in 4 topics
New to servers? Start here. Read these in order and the rest of the section will make sense.
- What is a VPS? How one physical server becomes manyA virtual private server is a slice of a real machine, cut out by a hypervisor. How the slicing works, what you get to yourself and what you share.
- vCPU vs CPU core: what you are really buyingCores, threads, vCPUs and dedicated cores explained, with what each means for a server under load.
- What happens when you open a website: DNS, TCP, TLS and HTTPEvery step between typing an address and seeing a page, what each one costs in round trips, and where a slow site usually loses its time.
- What is a DDoS attack? The three kinds, and what each one runs outVolumetric floods, protocol attacks and application attacks: what each exhausts, how it is launched, and why the kind matters for defence.
- Where should your server be? Latency, distance and the speed of lightWhy distance sets a floor on latency, how routes add to it, and how to pick a region for users spread across a continent.
Servers and cloud. How servers, virtual machines and the parts inside them actually work.
What is a VPS? How one physical server becomes manyA virtual private server is a slice of a real machine, cut out by a hypervisor. How the slicing works, what you get to yourself and what you share.Read the guideVPS, dedicated server or cloud instance: what actually differsThree names for renting compute, and the real differences between them: who shares the hardware, how you pay, and what happens when you need more.Read the guidevCPU vs CPU core: what you are really buyingCores, threads, vCPUs and dedicated cores explained, with what each means for a server under load.Read the guideHow much RAM does a server need? Memory, swap and the page cacheWhy free memory is wasted memory, what the page cache does, when swap helps and hurts, and how to read a server's real memory use.Read the guideNVMe vs SATA SSD vs hard disk for serversQueues, latency and throughput: how the three kinds of storage differ, and which workloads feel the difference.Read the guideBandwidth vs data transfer: Mbit/s, terabytes and what a 1 Gbit/s port meansPort speed and monthly traffic are different numbers. How they relate, how to convert between them, and how to estimate what you need.Read the guideWhere should your server be? Latency, distance and the speed of lightWhy distance sets a floor on latency, how routes add to it, and how to pick a region for users spread across a continent.Read the guide
Websites and apps. What sits between a visitor and your code, and how to run each piece.
What happens when you open a website: DNS, TCP, TLS and HTTPEvery step between typing an address and seeing a page, what each one costs in round trips, and where a slow site usually loses its time.Read the guideThe web server stack explained: nginx, PHP-FPM, app servers and databasesWhat each layer of a typical website stack does, how a request moves through it, and where caching fits.Read the guideDNS explained for server owners: records, TTLs and propagationHow a name becomes an address, what A, AAAA, CNAME and MX records do, and why a change seems to take hours to reach everyone.Read the guideSizing a database server: the working set, memory and disksWhy memory decides database speed, how to estimate your working set, and when disk speed or more cores start to matter.Read the guideWireGuard vs OpenVPN: how self-hosted VPNs workTunnels, keys and handshakes: how the two common VPNs work, where they differ, and what running your own involves.Read the guideServer backups that actually restore: 3-2-1, snapshots and dumpsThe difference between a snapshot and a backup, why a live database needs a dump, and how to prove a backup restores before you need it.Read the guide
Security and DDoS. How attacks work, what each one runs out, and what really stops them.
What is a DDoS attack? The three kinds, and what each one runs outVolumetric floods, protocol attacks and application attacks: what each exhausts, how it is launched, and why the kind matters for defence.Read the guideHow DDoS protection works: scrubbing, filtering and rate limitsWhere attack traffic is stopped, what upstream scrubbing can and cannot see, and why filtering close to the server matters.Read the guideHow to check a host's DDoS protection claimsTerabits, always-on, unlimited: what a hosting provider's DDoS claims mean, and how to check them yourself from public routing data before you buy.Read the guideSYN floods and SYN cookies, explainedHow the TCP handshake can be turned against a server, and how SYN cookies let it keep answering without keeping state.Read the guideAmplification attacks: how a small request becomes a huge replyWhy DNS, NTP, memcached and other UDP services get used to multiply attack traffic, and how spoofed sources make it work.Read the guideXDP and eBPF: filtering packets at the network driverHow eBPF runs verified programs inside the Linux kernel, why XDP is the fastest place to drop a packet, and what it is used for.Read the guideSecuring a new Linux server: what attackers try firstThe first things that hit a fresh server on the internet, and the handful of changes that stop most of them.Read the guide
Game servers. What makes a game server different to host, to size and to protect.
Tick rate and the main thread: why game servers want clock speedHow a game server simulates the world in ticks, why most of that work runs on one thread, and what that means for choosing hardware.Read the guideWhy game servers get DDoS attacks, and why generic protection strugglesWhy games attract attacks, why UDP game traffic is hard to filter, and what protection that understands the game protocol does differently.Read the guideGame server ports and firewalls: what to open and whyWhich ports a game server listens on, TCP versus UDP, query ports and RCON, and how to open exactly what players need.Read the guide
Questions these guides do not answer?
Ask in the chat on any page, or read the help center for step-by-step instructions on the Clouduxe panel.