Everything useful I know about kubectl

#1

Post by alexhwoods » Mon, Jul 05, 2021, 12:04 PM UTC

Everything useful I know about kubectl
atomiccommits.io

Re: Everything useful I know about kubectl

#2

Post by iechoz6H » Mon, Jul 05, 2021, 1:43 PM UTC

Break in case of Fire (i.e. rollback to the previous deployment version):

kubectl rollout undo deployment

Re: Everything useful I know about kubectl

#3

Post by alek_m » Mon, Jul 05, 2021, 1:57 PM UTC

Every time I'm starting a new service to run internally or reviewing something we have going, I find myself struggling to find the right instance type for the needs.

For instance, there are three families (r, x, z) that optimize RAM in various ways in various combinations and I always forget about the x and z variants.

So I put together this "cheat sheet" for us internally and thought I'd share it for anyone interested.

Pull requests welcome for updates: https://github.com/wrble/public/blob/main/aws-instance-types...

Did I miss anything?

Re: Everything useful I know about kubectl

#4

Post by secondcoming » Mon, Jul 05, 2021, 2:24 PM UTC

alek_m wrote: post #3

Every time I'm starting a new service to run internally or reviewing something we have going, I find myself struggling to find the right instance type for the needs. For instance, there are three families (r, x, z) that optimize RAM in various ways in various combinations and I always forget about the x and z variants. So I put together this "cheat sheet" for us internally and thought I'd share it for anyone interest…

Both AWS and GCP allow you to customise a machine's spec. You're not limited to the ones they offer.

Re: Everything useful I know about kubectl

#5

Post by loriverkutya » Mon, Jul 05, 2021, 2:34 PM UTC

secondcoming wrote: post #4

alek_m wrote: post #3

Every time I'm starting a new service to run internally or reviewing something we have going, I find myself struggling to find the right instance type for the needs. For instance, there are three families (r, x, z) that optimize RAM in various ways in various combinations and I always forget about the x and z variants. So I put together this "cheat sheet" for us internally and thought I'd share it for anyone interest…

Both AWS and GCP allow you to customise a machine's spec. You're not limited to the ones they offer.

Maybe I’m not 100% up-to-date with AWS Ec2 offerings, but as far as I’m aware, you can only choose from predefined instance types.

Re: Everything useful I know about kubectl

#6

Post by tut-urut-utut » Mon, Jul 05, 2021, 2:50 PM UTC

I would add one more important point about kubectl?

If you don't work at Google, you don't need a complexity of kubernetes at all, so better forget everything you already know about it. The company would be grateful.

Joke aside, trying to sell something to the masses that could potentially benefit only 0.001% of the projects is just insincere.

Pure CV pump and dump scheme.

Re: Everything useful I know about kubectl

#7

Post by dmitriid » Mon, Jul 05, 2021, 3:01 PM UTC

All that is good and dandy until you run a command and it spews a serialised Go struct instead of a proper error. And, of course, that struct has zero relationship to what the actual error is.

Example:

    The Job "export-by-user" is invalid: spec.template: Invalid value: core.PodTemplateSpec{ObjectMeta:v1.ObjectMeta{Name:"", GenerateName:"", Namespace:"", SelfLink:"", UID:"", ResourceVersion:"", Generation:0, CreationTimestamp:v1.Time{Time:time.Time{wall:0x0, ext:0, loc:(*time.Location)(nil)}}, DeletionTimestamp:(*v1.Time)(nil), DeletionGracePeriodSeconds:(*int64)(nil), Labels:map[string]string{"controller-uid":"416d5527-9d9b-4d3c-95d2-5d17c969be19", "job-name": "export-by-user", Annotations:map[string]string(nil), OwnerReferences:[]v1.OwnerReference(nil), Finalizers:[]string(nil), ClusterName:"", ManagedFields:[]v1.ManagedFieldsEntry(nil)}, Spec:core.PodSpec{Volumes:[]core.Volume(nil), InitContainers:[]core.Container(nil), Containers:[]core.Container{core.Container{Name:"....

And it just goes on.

The actual error? The job is already running and cannot be modified

Re: Everything useful I know about kubectl

#8

Post by nsxwolf » Mon, Jul 05, 2021, 3:03 PM UTC

I’d love to know the easiest way to answer this question: “what IP address and port is the microservice pod the CI server just deployed listening on?”

Re: Everything useful I know about kubectl

#9

Post by whalesalad » Mon, Jul 05, 2021, 3:27 PM UTC

nsxwolf wrote: post #8

I’d love to know the easiest way to answer this question: “what IP address and port is the microservice pod the CI server just deployed listening on?”

Why wouldn't that be determinstic? You should be using a service for that.

    kubectl get svc -l app=

Re: Everything useful I know about kubectl

#10

Post by imglorp » Mon, Jul 05, 2021, 3:28 PM UTC

tut-urut-utut wrote: post #6

I would add one more important point about kubectl? If you don't work at Google, you don't need a complexity of kubernetes at all, so better forget everything you already know about it. The company would be grateful. Joke aside, trying to sell something to the masses that could potentially benefit only 0.001% of the projects is just insincere. Pure CV pump and dump scheme.

This is getting downvoted for cynicism maybe, but I feel it's the most important advice here. Know /when/ to use Kubernetes.

It's very often the wrong tool to deploy our tiny app but many of us go along with it because it ticks some management boxes for various buzzwords, compliance, hipness, or whatever. Once you get out this hammer factory, it's a big and complicated one, so you will probably need a full time team to understand it and manage it. It's also a metric hammer factory, so you'll need to adapt all your other tooling to interoperate. Most of us can get by with lesser hammer factories, even k3s is less management.

If you just need to deploy some containers, think hard if you want to buy the whole tool factory or just a hammer.