Archive
Posts from 2016
A quick and easy way to rotate and resize images in Ubuntu Linux
I've been using the ImageMagick package for several years to resize and rotate images that I link to on my blog. Both operations are super easy to do with the convert utilities "-resize" and "-rotate" options. The following command will shrink an image by 50%: To rotate an image 90 degrees you can use "-rotate": Man convert(1) provides a TON more detail along with descriptions of numerous other conversion options.
$ read more →My path to bees and vegetables
A couple years back I purchased our first home. It was a "fixer upper" so I spent a year or two working on various projects. Once those were complete I decided to start raising honey bees and growing fruits and vegetables. This was one of the best decisions of my life and it it just as challenging as designing and troubleshooting complex computer systems…
$ read more →The importance of cleaning up disk headers after testing
Yesterday I was running some benchmarks against a new MySQL server configuration. As part of my testing I wanted to see how things looked with ZFS as the back-end. So I loaded up some SSDs and attempted to create a ZFS pool. Zpool spit out a "device busy" error when I tried to create my pool leading to a confused and bewildered matty…
$ read more →Debugging OpenLDAP ACLs
OpenLDAP provides a super powerful ACL syntax which allows you to control access to every nook and cranny of your directory server. When I'm testing advanced ACL configurations I have found it incredibly useful to add the "ACL" log option to the loglevel directive: When this option is set slapd will show you how it applies the ACLs to a given LDAP operation: This is super handy and will save you tons of time and heartburn when crafting complex ACLs.
$ read more →Troubleshooting vSphere NSX manager issues
This week I installed VMWare NSX and created a new NSX manager instance. After deploying the OVF and prepping my cluster members I went to create the three recommended controller nodes. This resulted in a "Failed to power on VM NSX Controller" error which didn't make sense. The package was installed correctly, the configuration parameters were correct and I double and tripled checked that the controllers could communicate with my NSX manager…
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