Jonny and the Cell (pt. 1)

My quest began, like so many others, while standing in front of my white board. I was slowly trying to identify something--something elusive--yet so simple was it that my failure to articulate it must have been born of the same difficulty one might have when trying to bring into focus the tip of one's nose, for it was its very proximity that prevented me seeing it...

Clearing the DNS cache in OS X

Every once in a great while, I find it necessary to flush my DNS cache. Usually, I only find it necessary to do this after making changes to DNS when at the office, but when attempting to diagnose some interesting Internet connectivity issues, it can occasionally come in quite handy.

I couldn't find anything obvious, but, after a moment's googling, I came across this little gem.

Anyway, here's the command:

dscacheutil -flushcache



Subnetting practice

I'm not sure why I haven't thought to post these before now, but here are a couple of links that may help if you're struggling with subnetting or just want to sharpen your skills.


ipcount: a handy tool for IP address allocation in OS X

If you happen to be in a position where allocating IP address blocks is a way of life, breaking up, say, a /21 into a bunch of /28's is not a difficult task--it just takes someone like me longer than I'd like.