Archive
Posts from 2017
Getting your kubernetes node names right
This past weekend while bootstrapping a new kubernetes cluster my kubeletes started logging the following error to the systemd journal: Secure kubernetes configurations use client certificates along with the nodename to register with the control plane. My kubeconfig configuration file contained a short name: But the hostname assigned to the machine was fully qualified: After re-reading the documentation there are two ways to address this. You can re-generate your certificates with the FQDN of your hosts or override the name with the kubelet '--hostname-override=NAME' command line option. Passing the short name to the kubelet '--hostname-override' option provided a quick fix and allowed my host to register: I need to do some additional digging to see what the best practices are for kubernetes node naming…
$ read more →Debugging a silly node application bug with the inspect interface
Last night while working on one of my many side projects I came across a relly weird Javascript issue. Here is an extremely simplified version of the code I was debugging: When the code ran it would return undefined for the object called obj even though console.log() showed it as a valid object inside the function: A seasoned Javascript developer would look at the code above and immediately see the flaw. Being new to javascript it wasn't immediately clear to me why this wasn't working. So, I figured this would be as good a time as any to learn how to use the inspect debugger to toubleshoot my issue…
$ read more →Disabling LLMNR on hosts that use the systemd stub resolver
While performing a routine audit of my desktop this morning I noticed that the systemd stub resolver was listening on TCP port 5355: TCP port 5355 is used for Link-Local Multicast Name Resolution (LLMNR) which is completely unnecessary for my set up at home. So I ventured off to /etc/systemd and came across the resolved.conf file. While perusing resolved.conf(5) I came across the following two configuration directives: LLMNR= Takes a boolean argument or "resolve". Controls Link-Local Multicast Name Resolution support (RFC 4794[1]) on the local host…
$ read more →Amazing tool for visualizing regular expression evaluation
Like most admins I use regular expressions pretty much every day. When I'm writing more complex expressions I've always wanted to visually observe what is actually happening. Well, to my surprise someone came up with an incredible online tool to do just that: Online regular expression evaluation website This is definitely one I will be adding to my bookmark bar!
$ read more →Managing Vsphere From The Linux Command Line
For the past year I've been working quite a bit with VMWare's vSphere virtualization suite. Managing vSphere through the web UI has been extremely frustrating though. The bugs, constant crashes and sluggishness have really impeded my ability to be productive. Being a command line user who loves to automate I decided to test out the govc command line utility to see if this would improve my experience…
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