I am trying to implement multi interface pods in azure kubernetes service. It seems like multus is not supported in aks(1). Is there any other way to achieve this. If possible what network policy and network configurations should be used?
This feature is not available today with Azure CNI. Also, there is no work around to implement multus or any other CNI like calico with AKS. Having said that, you can do provide your feedback here in this feature request form for its future availability.
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Given that I have a 24x7 AKS Cluster on AZURE, for which afaik Kubernetes cannot stop/pause a pod and then resume it standardly,
with, in my case, a small Container in a Pod, and for that Pod it can be sidelined via --replicas=0,
then, how can I, on-demand, best kick off a LINIX script packaged in that Pod/Container which may be not running,
from an AZURE Web App?
I thought using ssh should work, after first upscaling the pod to 1 replica. Is this correct?
I am curious if there are simple http calls in AZURE to do this. I see CLI and Powershell to start/stop AKS cluster, but that is different of course.
You can interact remotely with AKS by different methods. The key here is to use the control plane API to deploy your kubernetes resource programmatically (https://kubernetes.io/docs/concepts/overview/kubernetes-api/) .
In order to do that, you should use client libraries that enable that kind of access. Many examples can be found here for different programming languages:
https://github.com/kubernetes-client
ssh is not really recommended since that is sort of a god access to the cluster and its usage is not meant for your purpose.
Is there a way that "request per second" based scaling can be enabled on Azure Kubernetes Service?
HPA in AKS does allow horizontal pod scaling based on CPU and Memory constraints but there is no straightforward way to do it for - requests per second.
Is there a way to use advanced metrics in the metrics server bundled by AKS?
If you use Azure Application Gateway as your Ingress Controller, you can use its metrics for Horizontal Autoscaler. You can find documentation regarding the use case here. Note that this feature seems to still be in beta.
From whatever i read, i could not find a way to connect to master node in Azure kubernetes Service. I have a requirement to read some parameters like 'enable-admission-plugins' which is possible from master node. Is there any third party api available to get this info.
More specific i need to read the files 'kube-apiserver.yaml', 'kube-controller-manager.yaml'
No, this is not possible. Masters are managed by Microsoft and you dont have access to them. All the configurations are to be done through the AKS api (mostly when you create it).
Azure Kubernetes Service (AKS) makes it simple to deploy a managed
Kubernetes cluster in Azure. AKS reduces the complexity and
operational overhead of managing Kubernetes by offloading much of that
responsibility to Azure. As a hosted Kubernetes service, Azure handles
critical tasks like health monitoring and maintenance for you. The
Kubernetes masters are managed by Azure. You only manage and maintain
the agent nodes.
problem statement.
as per my understanding, we can run an elastic search, kibana and logstash etc as a pod in kubernates cluster for log management. but it is also memory heavy intensive application. AWS provides various managed services like Cloudwatch, cloud trail and ELK stack for log management.
do we have a similar substitute in Azure as well i.e. some managed service?
you can use AKS with Azure Monitor (reading). I'm not sure you can apply this to not AKS cluster (at least not in a straight forward fashion).
Onboarding (for AKS clusters) is really simple and can be done using various methods (portal included).
You can read more on the docs I've linked (for example, about capabilities).
Azure Monitor for Containers is available now and once integrated some cluster metrics as well as the logs will be automatically collected and made available through log analytics.
I see advantages of Kubernetes which include Rolling Deployments, Automatic Health check monitoring, and swinging a new server to action when an existing one fails. I also do understand that Kubernetes is not just for Docker.
So, that brings a couple of questions!
When Azure, and Service Fabric could provide all that I said (and beyond), why would I need Kubernetes?
Would it make sense for one to use Kubernetes along with Service Fabric for large scale deployments on Azure?
Let's look first at the similarities between Kubernetes and Service Fabric.
They are both cloud-agnostic clustering, orchestration, and scheduling software.
They can both be deployed manually, by you, to any set of VMs, anywhere.
There are "managed" offerings for both, meaning a cloud provider like Azure or Google Cloud will host a cluster for you, but generally you still own the VMs.
They both deploy and manage containers.
They both have rich management operations, such as rolling upgrades, health checks, and self-healing capabilities.
That's a fairly high-level view but should give you an idea of what and where you can run with each.
Now let's look where they're different. There are a ton of small differences, but I want to focus on two of the really big conceptual differences:
Application model:
Service Fabric allows you to orchestrate any arbitrary container or EXE (whether that's a small node.js app or a giant legacy application), and in that sense it is similar to Kubernetes. But overall it is more focused on application development specifically, with programming models that are integrated with the platform. In this respect, it is more closely comparable to Cloud Foundry than Kubernetes.
Kubernetes is focused more on orchestrating infrastructure for an application. It doesn't really focus on how you write your application. That's up to you to figure out; Kubernetes just wants a container to run, doesn't matter what's in it.
State management
Kubernetes allows you to deploy stateful software to it, by providing persistent disk storage volumes to containers and assigning unique identifiers to pods. This lets you deploy things like ZooKeeper or MySQL.
Service Fabric is stateful software. Service Fabric is designed as a stateful, data-aware platform. It provides HA state and scale-out primitives. So while Kubernetes allows you to deploy stateful things, Service Fabric allows you to build stateful things. This is one of the key differences that's often overlooked. For example:
On Kubernetes, you can deploy ZooKeeper.
On Service Fabric, you can actually build ZooKeeper yourself using Service Fabric's replication and leader election primitives.
Kubernetes uses etcd for distributed, reliable storage about the state of the cluster.
Service Fabric doesn't need etcd, because Service Fabric itself is a distributed, reliable storage platform. The system services in Service Fabric make use of this to reliably store the state of the cluster. This makes Service Fabric entirely self-contained.
The fact that Service Fabric is a stateful platform is key to understanding it and how it differs from other major orchestrators. Everything it does - scheduling, health checking, rolling upgrades, application versioning, failover, self-healing, etc - are all designed around the fact that it is managing replicated and distributed data that needs to be consistent and highly available at all times.
Please find below a good comparaison article about the difference between ACS and Azure Service Fabric:
https://blogs.msdn.microsoft.com/maheshkshirsagar/2016/11/21/choosing-between-azure-container-service-azure-service-fabric-and-azure-functions/
Could you please clarify what you refer to when you talk mentionne "AWS" ?
From a "developer level" solution could be statefull in both cases but it have a major difference from an Infrastructure point of view:
Docker + Kuberest is a "IaaS" oriented solution
Azure Service Fabric (if you are using Azure service) is a PaaS solution.
IaaS is, in general, more costly and have a more significant maintenance cost.
From a support point of view:
Azure Service Fabric is supported by Microsoft
Docker and Kubernetest are more open source oriented
Hope this help.
Best regards