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haydenk / devcontainer-jetbrains-vscode-codespaces.md
Last active April 12, 2026 02:49
Dev Containers: JetBrains + VS Code + Codespaces compatibility tips

Dev Containers: JetBrains + VS Code + Codespaces

Tips for getting the best JetBrains devcontainer experience while staying compatible with VS Code and GitHub Codespaces.

Core Concept: customizations is namespaced per tool

The devcontainer spec's customizations block is tool-namespaced — JetBrains config is ignored by VS Code/Codespaces and vice versa. They coexist in the same file without conflict.

@haydenk
haydenk / mikrotik-routeros-reference.md
Created April 9, 2026 02:20
MikroTik RouterOS command reference — system, interfaces, IP/routing, DHCP, DNS, firewall, NAT, mangle, QoS, VPN (IKEv2/WireGuard/L2TP/OpenVPN), CAPsMAN, IPv6, and network tools

MikroTik RouterOS Command Reference

CLI Basics

Navigation

/                           # Go to root menu
..                          # Go up one level
/ip address                 # Navigate to a menu directly
@haydenk
haydenk / iptables-nftables-reference.md
Created April 9, 2026 02:20
iptables & nftables reference — tables, chains, packet flow diagram, rule management, match options, targets, connection states, common recipes, and full nftables equivalents with translation table

iptables & nftables Reference

iptables

Tables and Chains

Table Built-in Chains Purpose
@haydenk
haydenk / wireshark-tcpdump-filters.md
Created April 9, 2026 02:20
Wireshark & tcpdump filter reference — display filter syntax, BPF capture filters, protocol/address/port/flag/HTTP/TLS/DNS filters, analysis filters, and tshark CLI usage

Wireshark & tcpdump Filter Reference

Wireshark Display Filters

Applied after capture. Rich syntax with protocol field awareness.

Operators

@haydenk
haydenk / linux-networking-commands.md
Created April 9, 2026 02:20
Linux networking commands — cheat sheet for ip, ss, tcpdump, nmap, dig, curl, ping, traceroute, nc, and ethtool with common flags and practical examples

Linux Networking Commands

ip — Network Configuration (iproute2)

Addresses

ip addr show                              # All interfaces and addresses
ip addr show eth0                         # Specific interface
ip addr show up                           # Only active interfaces
@haydenk
haydenk / hash-algorithms.md
Created April 9, 2026 02:20
Hash algorithm reference — cryptographic hash functions, password KDFs (bcrypt, Argon2id, scrypt, PBKDF2) with recommended parameters, MACs, digital signature algorithms, and output length table

Hash Algorithm Reference

Cryptographic Hash Functions

Algorithm Family Output Size Speed Status Primary Use
MD5 MD 128-bit (32 hex) Very fast Broken Legacy checksums only — do not use for security
SHA-1 SHA-1 160-bit (40 hex) Fast Broken Legacy; phased out of TLS, code signing, Git
SHA-224 SHA-2 224-bit (56 hex) Fast Acceptable Truncated SHA-256 variant; niche use
SHA-256 SHA-2 256-bit (64 hex) Fast Recommended General purpose; TLS, JWT, code signing, Bitcoin
@haydenk
haydenk / ssl-tls-reference.md
Created April 9, 2026 02:20
SSL/TLS reference — protocol version status, cipher suite anatomy, TLS 1.2/1.3 cipher suites, handshake diagrams, certificate types, key exchange algorithms, common attacks, and recommended Nginx config

SSL / TLS Reference

Protocol Version Status

Version Released Status RFC Notes
SSL 2.0 1995 Broken — disable RFC 6176 prohibits DROWN attack vector
SSL 3.0 1996 Broken — disable RFC 7568 prohibits POODLE attack
TLS 1.0 1999 Deprecated RFC 8996 BEAST; PCI-DSS prohibited since 2018
TLS 1.1 2006 Deprecated RFC 8996 Disabled in all major browsers (2020)
@haydenk
haydenk / http-headers.md
Created April 9, 2026 02:20
HTTP headers reference — request headers, response headers, Cache-Control directives, cookie attributes, and CSP directives with examples

HTTP Headers Reference

Request Headers

Header Description Example
Accept Media types the client can handle Accept: text/html,application/json;q=0.9
Accept-Encoding Compression algorithms the client supports Accept-Encoding: gzip, br, deflate, zstd
Accept-Language Preferred response language(s) Accept-Language: en-US,en;q=0.9,fr;q=0.8
Authorization Authentication credentials Authorization: Bearer
@haydenk
haydenk / wifi-ethernet-standards.md
Created April 9, 2026 02:20
Ethernet & Wi-Fi standards reference — 802.3 speeds/media/distances, cable categories, fiber types, 802.11 generations, channel plans, Wi-Fi security standards, and key wireless terminology

Ethernet & Wi-Fi Standards Reference

Ethernet (IEEE 802.3)

Standard Common Name Speed Medium Max Distance
10BASE-T Ethernet 10 Mbps Cat3 UTP 100 m
100BASE-TX Fast Ethernet 100 Mbps Cat5 UTP 100 m
100BASE-FX Fast Ethernet 100 Mbps Multimode fiber 2 km
1000BASE-T Gigabit Ethernet 1 Gbps Cat5e UTP 100 m
@haydenk
haydenk / tcp-flags.md
Created April 9, 2026 02:20
TCP flags reference — flag definitions, common combinations, three-way handshake and teardown diagrams, connection states, port ranges, and TCP options

TCP Flags Reference

Flag Definitions

Flag Bit Position Hex Mask Description
CWR 8 (MSB) 0x80 Congestion Window Reduced — sender reduced its congestion window
ECE 7 0x40 ECN-Echo — congestion was experienced (used in ECN negotiation)
URG 6 0x20 Urgent — Urgent Pointer field is significant
ACK 5 0x10 Acknowledgment — Acknowledgment Number field is valid