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I recently changed Internet providers from Comcast Business to Verizon Fios connection. As part of the Fios package, are TV Set Top Boxes (STB) which use coax for Video, and Internet via MOCA for the guide data. It made me curious, what kind of traffic were these things sending on the network? What would they be trying to access? And how hard would it be to DMZ these things off from the rest of my wired/wifi network given I have no idea what they are up to. Behold, a DMZ configuration Requirements: ...

For a while I had used Smokeping to generate pretty graphs of network latency between various hosts on my network. The downside with Smokeping was always getting it working. Did I configure my webserver just right? Did I remember to save the webserver configs so that the next time I set this up, things just worked? Did I install all the right Perl modules (and the right versions of each) so that Smokeping’s binary worked? Then there were the differences in operation depending on if I ran it on Linux, OpenBSD, or FreeBSD. There had to be a simpler solution. I’ve been dabbling in Go and Graphite as side projects at home for a while. Go was a language I’d been wanting to use more given its popularity where I work. Graphite was always this itch I scratched whenever I wanted to visualize machine and network statistics for the various machines on my network. I knew I could come up with a simple solution using these two pieces of tech. I wanted to start small. Smokeping provides graphs of minimum, maximium, average, and std deviation for round trip times, as well as packet loss. These are all statistics provided by the ping command line tool. Why couldn’t I just wrap ping in a Go binary, and send those data points off to Carbon for graphing in Graphite? I present the resultant Go binary and library. parallelping is a Go binary used to ping remote hosts, in parallel. If provided with a Carbon host and port, the data is shipped off to Carbon/Graphite. carbon-golang is a Go library used to take Carbon metrics and send them off to a Carbon Cache over TCP. I do admit I borrowed a lot of the logic from marpaia/graphite-golang, both because I couldn’t quite get that library to integrate as documented, but also because I wanted the learning experience of building my own Go-based TCP client. Both of these are my first non-trivial pieces of Go code. The more I spent time with Go the less I felt it’s barrier to entry was as high as anticipated (I’ve been mainly a Python person for many years). Further usage documentation for each bit of code can be found on their respective Github project pages, eventually. Enjoy!

A new year gave me an itch to scratch. For years I had been running a pretty standard setup when it came to blogging. Linode Apache Wordpress MySQL It was as vanilla a setup as one can get, running on a $10/month Linode instance out of their datacenter in Atlanta. I never used the VM much other than for keeping what was an almost-completely static blog. I never had any issues with it. I just wanted to try something new. ...

No one likes to do repetitive OS installs. You know the kind, where you are just clicking through a bunch of prompts for username, password, and partitioning scheme as fast as you can to quickly get to the point where you can get some work done. This scenario happens to me every time OpenBSD releases a new errata. As my OS of choice for firewalls/routers, I use a fresh OS install as the baseline for building a -stable branch of install set files. ...

Problem Statement: While OpenVPN has served me well over the past few years both for site-to-site and road-warrior style VPN connections, it always bugged me that I had to hack a config file, juggle certificates, and use a custom client that isn’t part of the base OS to bring up the links. My Android phone has a built-in L2TP/IPSec VPN client. My Macbook Pro OS X 10.9 laptop has both an IPSec and L2TP VPN client GUI wrapped around racoon. I run OpenBSD as my firewall/router gateway at home. There must be a solution here. ...