Cheat sheets, study guides, and practice tests built by engineers with real certifications.
MikroTik CLI commands are the terminal commands you type into RouterOS to set up a router. This free PDF gives you the working commands for DHCP, NAT, firewall rules, routing, bridging, VPN tunnels, failover and hotspot, each with a ping test from a practice lab.
The most common ports are 80 (HTTP), 443 (HTTPS), 22 (SSH), 21 (FTP), 25 (SMTP), 53 (DNS), 67 and 68 (DHCP), 110 (POP3), 143 (IMAP) and 3389 (RDP). This free PDF explains each one with its port number, how it works and a real example.
The core Huawei router commands for an AR lab are system-view, sysname, interface, ip address, ospf 1, display ip routing-table and save. This free PDF puts SSH, PPP with CHAP and OSPF area 0 in paste-ready order for two Huawei AR routers.
Fourteen network troubleshooting commands cover almost every connectivity problem you'll hit, on Windows, PowerShell or Linux. This free cheat sheet lists each one with its exact syntax, what the output actually means, and the order to run them in, so you stop guessing and start isolating the fault in minutes. Network Troubleshooting Tools You Already…
Need a Cisco commands cheat sheet that doesn't stop at the basics? This one covers over 200 IOS commands across switches and routers, grouped by topic so you're not hunting through a 12-page manual mid-lab. Hostnames and passwords. VLANs and trunking. OSPF, EIGRP and RIP. ACLs, NAT, DHCP, PPP and Frame Relay. If it's a…
Free network topology types PDF diagram set. Star, mesh, bus, ring, tree and hybrid layouts explained with pros, cons and real network examples. There are six network topology types you'll actually run into: bus, star, ring, mesh, tree and hybrid. Each one lays out how devices connect, and that layout decides speed, cost, and how…
Full CIDR table, /8 to /32: subnet mask, wildcard mask, total hosts, usable hosts - Powers-of-2 host reference - IPv4 classes A to E, private ranges, loopback - Six subnetting shortcut tips - Per-prefix "how many usable hosts" Q&A block
The page copy in `01-page-content.md` describes a 20-question practice test weighted to the real exam blueprint. That test doesn't exist as a file yet, the sent PDF is someone else's platform and someone else's attempt, not ours to reuse. This is the spec for what needs writing before the download behind this page is real.
It's 27 pages of CCNA 200-301 study notes with the Packet Tracer commands underneath every concept. All six exam domains: networking fundamentals, subnetting with the magic-number trick, VLANs and trunking, router-on-a-stick, STP, EtherChannel, static routing and OSPF, DHCP and NAT/PAT, ACLs and port security, wireless, and the automation topics.
This is a free 47-page PDF written by a working service provider network engineer, not a vendor marketing team. Every recommendation comes with the actual configuration, and most come in all three flavours: IOS, IOS-XE and IOS-XR side by side. If you're building an MPLS core, prepping for CCNP Service Provider, or you inherited a network someone else tuned badly, this is the reference you keep open in a second tab.
It's 50 CCNA-level interview questions with short, say-it-out-loud answers. OSI model, subnetting, VLANs and trunking, STP, DHCP and DNS, NAT and PAT, OSPF and BGP, ACLs, HSRP, QoS, and the troubleshooting questions that come up in every first-round screen. One question per block, one tight answer under it. Built for people walking into a junior network engineer or NOC interview in the next two weeks.
Free OSI model cheat sheet PDF. All 7 layers with functions, PDUs, devices and protocols, plus mnemonics and an OSI vs TCP/IP map.
