Blog
Troubleshooting write-ups, decisions with real numbers, and the occasional "here is what the vendor did not tell you". Each one names its editor, and every command and figure in it is traced to the documentation or the standard that defines it.
A write-up of one problem: the symptom as the ticket described it, the commands that locate it, and the fix. Every command and every figure traced to the vendor documentation or the standard that defines it, never to another summary.
Each note opens with the symptom in the words of the ticket, then a 30-second proof, then a numbered checklist. Copy the commands; the numbers to remember are in a box at the end.
Reader tickets, our own on-call weeks and the quotes MSPs send us. Send yours through the contact page; if we reproduce it, you get the credit.
Networking notes
2 notes, newest firstWhy a 1500 byte packet dies inside an IPsec tunnel, the two commands that prove it in under a minute, and the MSS clamp that fixes it for good.
The same name answers twice, and which answer a laptop gets depends on which resolver the tunnel handed it. Here is how to prove it in two commands and fix it so it stays fixed.