Archive
Posts from 2020
Zookeeper now has native Prometheus metrics support
As a long time Kafka, Zookeeper, and Prometheus user, I have been utilizing the JMX exporter to gather operational metrics from my Zookeeper and Kafka clusters. Having to bolt on an additional component is never fun, so I was delighted to see that Zookeeper 3.6.0 added native Prometheus metric support. Enabling it is as easy as adding the following lines to your zoo.cfg configuration file: The included metrics rock, and there are now dozens of additional USEFUL metrics you can add to your dashboards. Hopefully Kafka will take note and provide native Prometheus metrics in a future release.
$ read more →Using node local caching on your Kubernetes nodes to reduce CoreDNS traffic
Kubernetes 1.18 was recently released, and with it came a slew of super useful features! One feature that hit GA is node local caching. This allows each node in your cluster to cache DNS queries, reducing load on your primary in-cluster CoreDNS servers. Now that this feature is GA, I wanted to take it for a spin…
$ read more →TRIM support is enabled by default in Fedora 32
As a long time Fedora user, I like to keep up with the planning discussions that go into each release. These discussions are super useful for understanding what is coming to Redhat Enterprise Linux and CentOS. One feature I've been keeping my eye on is the FSTRIM enabled by default feature. Using TRIM can free unused space on your storage arrays, and is especially important if you use thin provisioned storage devices…
$ read more →Disabling cron jobs globally on CentOS machines
As a long time CentOS user, I've always winced when I took ownership of new systems with e-mail notifications enabled. Whether this was through setting MAILTO to a distribution list, or using the default and sending it to the user who created the job. Having cron send mail has woken me up more than once when /var/spool/* filled up. Give the awesome searching capabilites that come with solutions like Elasticsearch, Loki, and Gray log, I now turn cron mailing off on all of my systems…
$ read more →Managing multiple Kubernetes resources by label
Kubernetes labels are super useful. If you aren't familiar with them, a label is a key/value pair assigned in the metadata section (either metadata.labels, or spec.template.metadata.labels) of a deployment manifest. The following example assigns three key/value labels to a deployment: Labels get super useful when you need to apply an action to multiple resources. Actions can include get: Which will get all pods with the label "app=nginx"…
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