I'm trying to run a Minio Cluster using the Jelastic template, however when attempting to activate the firewall on one of the nodes I'm greeted with the message "Firewall is not supported on this node."
screenshot
Firewall is only supported on official images from Jelastic.
When you use a custom docker image for your node, you won't be able to use the Jelastic Firewall on it. You have to manually configure the iptables.
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I have several Windows servers available and would like to setup a Kubernetes cluster on them.
Is there some tool or a step by step instruction how to do so?
What I tried so far is to install DockerDesktop and enable its Kubernetes feature.
That gives me a single node Cluster. However, adding additional nodes to that Docker-Kubernetes Cluster (from different Windows hosts) does not seem to be possible:
Docker desktop kubernetes add node
Should I first create a Docker Swarm and could then run Kubernetes on that Swarm? Or are there other strategies?
I guess that I need to open some ports in the Windows Firewall Settings of the hosts? And map those ports to some Docker containers in which Kubernetes is will be installed? What ports?
Is there some program that I could install on each Windows host and that would help me with setting up a network with multiple hosts and connecting the Kubernetes nodes running inside Docker containers? Like a "kubeadm for Windows"?
Would be great if you could give me some hint on the right direction.
Edit:
Related info about installing kubeadm inside Docker container:
https://github.com/kubernetes/kubernetes/issues/35712
https://github.com/kubernetes/kubeadm/issues/17
Related question about Minikube:
Adding nodes to a Windows Minikube Kubernetes Installation - How?
Info on kind (kubernetes in docker) multi-node cluster:
https://dotnetninja.net/2021/03/running-a-multi-node-kubernetes-cluster-on-windows-with-kind/
(Creates multi-node kubernetes cluster on single windows host)
Also see:
https://github.com/kubernetes-sigs/kind/issues/2652
https://hub.docker.com/r/kindest/node
You can always refer to the official kubernetes documentation which is the right source for the information.
This is the correct way to manage this question.
Based on Adding Windows nodes, you need to have two prerequisites:
Obtain a Windows Server 2019 license (or higher) in order to configure the Windows node that hosts Windows containers. If you are
using VXLAN/Overlay networking you must have also have KB4489899
installed.
A Linux-based Kubernetes kubeadm cluster in which you have access to the control plane (see Creating a single control-plane cluster with kubeadm).
Second point is especially important since all control plane components are supposed to be run on linux systems (I guess you can run a Linux VM on one of the servers to host a control plane components on it, but networking will be much more complicated).
And once you have a proper running control plane, there's a kubeadm for windows to proper join Windows nodes to the kubernetes cluster. As well as a documentation on how to upgrade windows nodes.
For firewall and which ports should be open check ports and protocols.
For worker node (which will be windows nodes):
Protocol Direction Port Range Purpose Used By
TCP Inbound 10250 Kubelet API Self, Control plane
TCP Inbound 30000-32767 NodePort Services All
Another option can be running windows nodes in cloud managed kuberneres, for example GKE with windows node pool (yes, I understand that it's not your use-case, but for further reference).
I have a simple one master (Ubuntu 1604), one worker (Windows Server 1803) Kubernetes cluster running in AWS. I am using Flannel for networking.
I have been able to deploy windows containers using kubectl from the master without issue. Deploying multiple pods shows they are able to talk to each other. But I am not able to ping or curl the pods from even the Kubernetes windows node host, or from the open internet. Also, the pods are not able to communicate with the outside internet either. (Can't curl external DNS names or even IP addresses.)
Side note: Deploying the same image directly with Docker on the Windows node is able to connect to the internet and be accessed over the internet.
I used the following setup from Microsoft, which uses kubeadm, flannel and scripts from Microsoft SDN repo.
https://onedrive.live.com/view.aspx?resid=E2B6765015E5FA01!339&ithint=file%2cdocx&app=Word&authkey=!AGvs_s_hWs7xHGs
It is my understanding that on Windows the host network interface is not connected to the Kubernetes network interface by default, but the Docker network uses the default interface. Which might be why docker deployments can be accessed but Kubernetes deployments cannot.
However, I haven't found info on connecting these networks when using Flannel for pod communication on Windows.
I can add any logs or config info that anyone thinks is useful.
Any thoughts? Thanks for your help!
More Details:
I am looking into this: https://unofficial-kubernetes.readthedocs.io/en/latest/getting-started-guides/windows/ which describes connecting network interfaces between the Windows default and Kubernetes, but does not seem to rely on the same Flannel Host-GW model I used to set this up.
I'm currently experimenting with Swarm Services with Docker for Windows. The new Win10 Insider build supports overlay networking for Windows containers and I was pleased to see my IIS service actually starting. The only issue i came across is that i can not reach the service in the browser, despite trying multiple things such as different ports and networks. The command issued is as following:
docker service create --name webfarm -p 80:80 microsoft/iis
I have also tried to use the --network flag to try different networks and I have made sure to test all IP addresses visible in the docker service inspect webfarm command.
docker service ps webfarm does indicate that my service is in state RUNNING and does not have any errors, so i don't know what else i can try. Especially since these commands worked fine on Linux with Apache.
I was wondering if anyone has been able to successfully create a service using Windows Containers on the Windows Insider build (15046), and if so, how?
Never mind, i found this actually is not supported yet.
The following source states:
"At the moment only DNS round robin is implemented as described in the Microsoft blog post. You cannot use to publish ports externally right now. More to come in the near future." (https://stefanscherer.github.io/docker-swarm-mode-windows10/)
And indeed, the blogposts states the following:
"Currently, Windows supports DNS Round-Robin load balancing between services. The routing mesh for Windows Docker hosts is not yet supported, but will be coming soon. Users seeking an alternative load balancing strategy today can setup an external load balancer (e.g. NGINX) and use Swarm’s publish-port mode to expose container host ports over which to load balance." (https://blogs.technet.microsoft.com/virtualization/2017/02/09/overlay-network-driver-with-support-for-docker-swarm-mode-now-available-to-windows-insiders-on-windows-10/)
I guess I'll have to wait for this feature, in the meantime I will use the alternative.
I am using Google Compute Engine to run Mapreduce jobs on Hadoop (pretty much all default configs). While running the job I get a tracking URL of the form http://PROJECT_NAME:8088/proxy/application_X_Y/ but it fails to open. Did I forget to configure something?
To elaborate on the option Amal mentioned in the other answer of using the "external ip address" of your Google Compute Engine VM, you can obtain the external IP address by running gcloud compute instances describe --zone <your zone> <your master hostname> and looking for natIP.
To open port 8088, you'll have to set up a firewall rule opening that port, likely on your default Google Compute Engine network. You'll want to specify a your.ip.address.here/32 address in the --source-ranges to restrict incoming traffic to just your local machine dialing into your VM, otherwise the anyone in the IP source-ranges would be able to access your Hadoop pages.
If you had used bdutil to turn up your cluster, there's an alternative way which is much easier and more secure; simply run
bdutil <your flags used in deployment, like -e hadoop2, --prefix, etc.> socksproxy
to open SSH with dynamic port forwarding to use as a SOCKS5 proxy that your browser can point to. If you're running on Linux or Mac and have Chrome or Firefox installed, bdutil should also print out a copy/paste command for starting a fresh isolated browser pre-configured to use the socks proxy so that you can click through all the useful links.
If bdutil didn't print out a browser command or you didn't use bdutil, you can also run and configure your SSH socks proxy using these instructions. An SSH-based socks proxy is more secure than opening up firewall ports, and also allows the Hadoop page links to work (otherwise you have to keep manually replacing the hostnames with the external IP addresses).
One correction. You are using YARN. So there is no jobtracker. Jobtracker is present in hadoop 1.x. In YARN, the processing layer became a generic framework and the jobtracker got replaced with Resource manager and application master. The UI that you mentioned in the question was of Resource Manager.
For your problem, try the following tips.
Use the public ip address of the resource manager instance instead of PROJECT_NAME.
Check whether the 8088 port is opened for accessing it from outside.
Another (more secure) way to do this is to use gcloud compute to make an ssh tunnel to your deployment, and then launch Chrome though it.
$ gcloud compute ssh clustername --zone=us-central1-a --ssh-flag="-D 1080" --ssh-flag="-N" --ssh-flag="-n"
You will need to replace clustername with the name of your deployment, and change the --zone if necessary.
From there, you can launch Chrome through it and then reach the hadoop job tracking URL.
$ chrome --proxy-server="socks5://localhost:1080" \
--host-resolver-rules="MAP * 0.0.0.0 , \
EXCLUDE localhost" --user-data-dir=/tmp/clustername
I spun up a Mesosphere cluster on Digital Ocean (development) and it's not allowing me to allow external (non vpn) connections to containers or apps. How can this be solved ?
To ensure that the world doesn't have access to your cluster normally, there have been iptables rules installed. By default, these allow full access inside the cluster and nothing externally.
If you're interested in running real applications, I'd recommend the following:
Put HAProxy on a single node.
Setup the haproxy-marathon-bridge script.
On the same box that you installed HAProxy on, setup iptables to allow access to the port that HAProxy is listening on.
By doing this, you'll have a single place to refer to when giving access to applications running on your Mesos cluster. No matter where the app or container is scheduled (with marathon), you'll always be able to reach it via. haproxy.