I had this interesting question the other day. Someone had a file with two columns of data in it. They wanted to assign each column to a different variable and then take action using those two variables. Here's the example I wrote for them:

IFS=$'\n';
for LINE in $(cat …

Quick and dirty OpenSSH configlet here. If you have a set of hosts or devices that require you to first jump through a bastion host, the following will allow you to run a single ssh command:

Host *
    ProxyCommand ssh -A <bastion_host> nc %h %p

Change the Host * line to best …

I was recently asked to take two lists and interleave them. Although I can not think of a scenario off the top of my head where this might be useful, it doesn't strike me as a completely silly thing to do. StackOverflow's top answer for this problem uses itertools.chain …

Things have changed quite a lot since this post was originally written in 2016. Currently, I would recommend switching over to making asynchronous calls via aiohttp.

One of my scripts that makes an API call has been failing silently lately. It appears that the connection is timing out, but I …

I've been getting the following error from cron.daily in my inbox lately:

/etc/cron.daily/apt:
Cache has broken packages, exiting

That's an annoying email to get everyday. I decided I would apt-get clean and that would probably fix the problem:

$ sudo apt-get clean
$ sudo apt-get dist-upgrade
Reading package …

I use Pingdom's free service to monitor slaptijack.com. Apparently, late Friday night, oom-killer decided that the server needed more memory and took out the MySQL server. To make matters worse, I missed the alarm from Pingdom, and slaptijack.com was down for pretty much all of Saturday. The fact …

Ever so often, something changes on the network, and you find that your .ssh/known_hosts file has gotten out of date. Usually this happens after an upgrade or device change. You'll get the rather ominous warning that REMOTE HOST IDENTIFICATION HAS CHANGED!

If you are confident that someone isn't doing …

While updating the TCP tuning parameters on one of my OS X 10.11 servers, I noticed that my existing OS X TCP Performance Tuning page had gotten out of date. The page was nearly eight years old, so it is no surprise that happened. I updated the page in …

I have written previously regarding using Redis for Magento session storage. You can get the same benefits of using Redis for session storage (reduced disk I/O, automatic key eviction) for any PHP application by making a quick change to a couple of settings in your php.ini. I assume …

Although I do not use Exim myself, I have clients that do. Recently, we noticed that it was taking more than 20 seconds for their SMTP banner to display when initiating checks from the monitoring server. Connecting to the server locally (on any interface IP address) did not suffer the …