Networking
Merging Overlapping Subnets
Once upon a time there was a single AWS account. In this AWS account was several regions but a single VPC. To make sure expansions into other regions was …
Reflashing Cisco Catalyst With XMODEM
One of the Cisco Catalyst 3750 I had to work on recently had it's flash completely wiped. When this happens you can only flash the filesystem using the XMODEM …
AWS Elastic IP Details
Sometimes it becomes important to understand how your cloud provider implements certain networking details. While working through an issue in AWS I needed to …
Fighting IPSec on AWS
IPSec is a well known and well understood protocol that is pretty easy to get setup and going... Most of the time. While setting up an IPSec tunnel to an AWS …
Quick and Silent Gigabit Packet Interception
I regularly find myself inspecting traffic on Linux systems. Usually I'm already on the client or server when doing this (such as when diagnosing weird low …
Using OpenWRT's Dnsmasq as a TFTP Server
I recently re-flashed my primary router to a newer version of OpenWRT and attempted to follow my own directions written in an earlier blog post to add PXE …
Configuring PXE Booting on OpenWRT
I needed to support PXE booting on my home network. I use OpenWRT as my main router and DHCP server and it took me a bit of searching how to configure the BOOTP …
NFS
NFS (Network File System) allows sharing directories between Linux systems over a network. NFSv4 is the current recommended version and simplifies things by …
Network
found top level header in "/notes/linux/network/" that didn't match meta title ("Network Configuration" != "Network")Modern Linux …