Troubleshooting network problems in local area networks
My experience with system administrators on all platforms is that the network is something of a mysterious think. When it all works, it is beautiful. When it fails....
Despite what the elites tell you about the OSI stack, networks have 4 levels: physical (wires, or radio), internet (IP), transport (TCP, UDP, SCTP), application.
I'm going to talk about troubleshooting from the bottom layer up:
- Diagnosing physical layer problems: ethernets, Wifi, ARP
- Failure modes in IPv4 and IPv6 (if possible - requires an IPv6 infrastructure, which might not be available). Routing failures. Name resolution failures.
- Transport problems (TCP, UDP)
- Application problems (HTTP, HTTPS, SSH - depending on how much time I have left)
- How to prepare for network failures using documentation
Short Link: http://lfnw.org/node/4486