Technology Insights

sudo: unable to resolve host

I ran in to the weirdest error today.   “sudo: unable to resolve host”. I got this error even running as root which was the really weird part.  I was especially confused because I have been running Linux as my main OS for the better part of 10 years and have never run into this issue. Turns out the solution is very simple and almost elementary however I decided to make a quick post about it.

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Technology Insights

Firefox Plugin To Analyze Web Page Speed And Page Speed Activity

Earlier today I was looking around Google’s Webmaster Tools site which allows you to add various web sites and analyze data obtained via the Googlebot search engine spider. If you are not familiar with the Google Webmaster Tool site then click here to explore all of the data that is available to you for each of your web sites. Anyhow in the process of looking around the Webmaster Tools site I noticed a Firefox plugin called Page Speed in the Labs portion of the Webmaster Tools site. This plugin provides similar functionality to Safari’s Web Inspector when combined with the required Firebug Firefox plugin. Below is information on installing the Google Page Speed Firefox plugin as well as basic usage information including some screenshots of the plugin in action.

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Technology Insights

Error installing memprof: checking for gelf_getshdr() in -lelf… no

I received the below error when attempting to install the memprof gem on a CentOS Linux server. The errors pointed out below could occur when attempting to install other packages as well though. Below I display a summary of the error output, the entire error output, and information on what to install to resolve the error. I noticed that on one server where the memprof gem installed without issue the gelf.h file was in the /usr/include/ directory however are the server that produced the error gelf.h was not installed.

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