mkubectx - single command across all your selected kubernetes contexts

Probably the most popular container in kubernetes environment. Container image is really small:

$ docker images | grep -i pause
k8s.gcr.io/pause                          3.2                 80d28bedfe5d        2 months ago        683kB

Codebase is also small pause. According to source code it is responsible for doing pretty... nothing, except of dealing ...

Default kubelet container runtime configuration use docker as CRI. Containerd has another implementation of CRI, it should fullfill the same requirements as docker so ie. it's responsible to maintain container images. Containerd extends its functionality by using plugins, one of them is cri. To interact with containerd we can ...

In a few words Container Runtime Interface is the answer to this questions. But we are going a little bit deeper. First of all what is CRI ? CRI is one of the most mature interface in kubernetes, it's a bridge between kubelet and container runtime. . Creating such interfaces in ...

Kubectl is an entrypoint for maintaing k8s clusters, you can find a lot useful switches to extract data. For example to get all containers images, just use:

$ kubectl get pods --all-namespaces -o go-template --template="{{range .items}}{{range .spec.containers}}{{printf \"%s\n\" .image}}{{end}}{{end}}"

Lots of switches ...

Easy alternative to fdisk and partprobe when resizing partition to its maximum. Extensively used in cloud environments (i.e. cloud-init).

https://www.systutorials.com/docs/linux/man/1-growpart/

Tracers is nice extension to one of my favourite tool sysdig to troubleshooting problems. Using damn simple approach of writing tags to /dev/null, give an idea about your app's health. More performing than popular statsd to measure duration, because of low overhead ca. 1 microsecond per tracer. Moreover ...

One of the easiest way to visualize your app internal performance metrics on demand is too use pretty new standard described in:

https://www.w3.org/TR/server-timing/

combined it with for example Chrome Developers Tools from version 65. More practically with Python Flask app:

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Looking for reason why some processes cannot be killed, you probably reach to process state called uninterruptible. Nice explanation:

https://stackoverflow.com/questions/223644/what-is-an-uninterruptable-process

Linux ps command shows which process is in that state by pinning D in process output list. But on which step this process really stuck ...

Writing bash scripts is a daily basis for sysops/devops teams. Some parts of each written script stay the same like being verbose for easy debugging, so it's good to have some templates. One of them helps us to deal with logs, which are written to log file and ...