Bottom Line Up Front
az vmss run-command can be used to influence a change or gather information on/from your VMs without gaining direct access to them. When executed a shell command is run as an admin against the VM.
This can be used to gain emergency access, indirectly, to manage the VM if for some reason you’re unable to do so in other ways. This includes account management, IE: Creating accounts, resetting passwords, getting network info and so on.
Bottom Line Up Front
Understand your IOP and Throughput peak needs before you create the cluster. Let the data dictate your requirements.
Understanding an applications resource consumption is vital to ensuring proper performance in a Kubernetes cluster. This is part 1 of 3 and we will focus on looking at our application at rest to understand the resource impact the application has without any load
Optimizing cluster performance isn’t something that is unique to the Azure Kubernetes Service. All the concepts and ideas in this article stretch not only to every cloud provider and K8 application but all applications in general.
There are three other articles I wrote that will help you understand why these concepts are important in Kubernetes. …
Ramblings from a veteran
I have gone through many interviews in my nearly 20 years in the IT field. Many of them I had little interest in before even accepting an interview. I know some of you might be thinking “why waste everyone's time if you’re not interested?”. Well simply put, its an interview and it goes two ways. I am just as unsure if I am interested in working with them as they are with me.
An interview isn’t just about the candidate selling themselves. The company must also sell to the candidate. It’s a fine balance of yes…
Be like water, my friend.
Most of you who consume Kubernetes have likely already heard the news that Kubernetes is going to deprecate Docker support in an upcoming release. Surprisingly I have seen quite a bit of panic from both consumers who host their own clusters and from those who use hosted solutions like AKS and GKE. Specifically because some how its getting around the deprecation is happening on version 1.2.
The only thing that consumers should notice in 1.2 is a kubelet warning that gets logged if Docker is the current runtime, the actual deprecation is not expected to…
Knowing where you’re going by knowing where you’ve been
So bonus points for anyone who knows that reference. Not like…cool points or anything…just…points. ;) One of the most water cooler talked about things I tend to hear is around monitoring VM performance. Microsoft has all kinds of crazy awesome tools to look at how a VM is performing but what about the consumers?
Believe it or not, most of the resources Microsoft evaluates comes from the same source that is available to all customers directly from within the portal. Now depending on the type of compute resources you have (IE…
How much vs how little
In my previous article I discussed Resource Quotas and gave an example of how and why someone may want to consider using them on their cluster. You might have be thinking to yourself in the last article “Well that's nice you can limit a namespaces resources but what happens if someone creates a pod that just takes it all up at once?”. …
Limiting resource consumption for multi-team clusters
Always remember to evaluate your needs and requirements against what resources you have available to determine your best approach.
When limits are not enough
In my previous article I discussed Resource Request and Limits to help people understand the importance of setting appropriate pod specs to avoid over saturating nodes. What if the cluster is shared across multiple teams or developers? How do you prevent one single person from taking up all the cluster resources?
Many teams have limited resources and specific resource needs that must be shared
In clusters like this setting pod…
How much do I need vs how much can I use
One of the most important things Kubernetes can do for you is to help ensure workloads are running on nodes capable of handling their resource requirements. Setting proper requests and limits can help prevent you from over saturating your nodes which would inevitably result in poor performance.
Definition of the amount of resources K8s will guarantee to a pod hosted on a node
Resource Requests define the amount of resources that K8s will guarantee to a pod. To some degree you could think of this definition as the minimum…
Take advantage of the Diagnose and Solve Problems Blade within the portal to help troubleshoot common issues with your AKS Cluster
A portal based tool that can be used to diagnose and troubleshoot common and sometimes obscure issues to help you save time
Kubernetes is a fairly large beast. Even when using hosted solutions like AKS there are still things that can wrong that you may need to troubleshoot. Microsoft has invested a significant amount of time into writing code that helps detect issues so you don’t have to.
The Diagnose and Solve Blade for AKS is an ever evolving…
Builder and breaker of things, technology dude, all opinions are my own.