Author Archives: jpk
301 redirects for URL typos for domains that have multiple sub-domains
Anyone who has tried to brand themselves or their company with a domain name knows that they should buy multiple domain names that are similar (e.g. .com, .net, .org) but they should also buy misspelled/mistyped variants of their domain names … Continue reading
Mac OS X Lion, Terminal and ssh: how to start ssh-agent at login
As a freelance sysadmin, I use Mac OS X’s Terminal.app to connect to a lot of different Unix and Linux servers–I will frequently have a dozen or two (or sometimes three) terminals open to different machines. This is one of … Continue reading
shell scripting pitfall: string/number conversions
I create quite a few WordPress installs for my partner, Morgan, to develop from, and we have a non-trivial number of changes we implement for each new WordPress install. I wrote a simple install script that does everything so that … Continue reading
If you have a good systems administrator, you’ll never know he’s there
I recently wrote about what a systems administrator does. I talked about how being a good systems administrator requires vigilance and foresight: to make sure that servers are always running reliably, I have to be able to predict what might … Continue reading
What does a freelance systems administrator do anyway?
Everyone who uses the internet relies on systems administrators, and yet one of the biggest challenges of being a freelance systems administrator is explaining what I do. Well, the shortest answer is, “A systems administrator takes care of servers. Not … Continue reading
Server problem detection: IO problem on old Linux kernel
As a freelance Linux systems administrator, I see a lot of odd problems come up. Some I can easily solve using just the things I know (making it appear to be magic), and others require a lot of sleuthing work, … Continue reading
SSH public keys, or, how not to expose a password
As an independent Linux/Unix consultant, I am often asked to work on machines that I have never used before, and so I need a password to log in. While I can be given a password over the phone, that frequently … Continue reading
Home Computer Security Tips for Corporate Professionals
Your IT department has probably locked down your computer at work with all sorts of security precautions, given you strict guidelines about how to choose passwords and how often to change them, and provided backups and fail-safes to make sure … Continue reading
Reboot your Mac twice and call me in the morning
My Apple MacBook Pro (mid-2010 Core i7 model) has been having intermittent hard lockups and display corruption for about 6 months now; it used to happen about three times a month, and results in a screen that looks like this: … Continue reading
Fun way of finding the decryption speed of your CPU
I was recently setting up a new server that has a pair of the Intel Nehalem CPUs (similar to the Core i7) based Xeons (X5670, running at 2.93GHz). These new CPUs have instructions for AES encryption built into the hardware, … Continue reading