Dears,
Sorry may be a basic question for some of you. If i have a Vsphere Environment and i am allowed to access only 2 Virtual machines inside them. Can I set kubernetes cluster with 1 VM as master and 1 VM as Minion without interacting with the hypervisor or the Vsphere center ?
In this case what are the requirements
I already set up an environment in my Laptop but i should define a host only network in Virtualbox and define the machines also for the host ? should that be the same in case of Vsphere ?
There are some requirements for Kubernetes cluster. According to the official documentation it is necessary to have:
One or more machines running one of:
Ubuntu 16.04+
Debian 9
CentOS 7
RHEL 7
Fedora 25/26 (best-effort)
HypriotOS v1.0.1+
Container Linux (tested with 1800.6.0)
2 GB or more of RAM per machine (any less will leave little room for your apps)
2 CPUs or more
Full network connectivity between all machines in the cluster (public or private network is fine)
Unique hostname, MAC address, and product_uuid for every node. See here for more details.
Certain ports are open on your machines. See here for more details.
Swap disabled. You MUST disable swap in order for the kubelet to work properly.
Also, IP subnets for Services and for Pods must not interfere with IP subnets in the same VPC.
To set up Kubernetes cluster it is enough to have SSH access to VMs. Additional network interfaces are not required.
If you already have VMs, the most convenient tool for cluster creation is kubeadm. Please, consider reading the following part of official documentation:
Creating a single master cluster with kubeadm
Related
Whenever I try to run the Kubernetes cluster from the master’s machine using the below command, my system hangs and gets very slow and I even cant open explorer, or firefox. I have two VM with network configuration NAT and Host-only adapter.
kubeadm init --apiserver-advertise-address=<ip-address-of-kmaster-vm> --pod-network-cidr=192.168.0.0/16
Any help is highly appreciated
As was discussed in comments, the root cause of the issue was not enough resources available in this VirtualMachine.
In Kubeadm documentation, minimal requirements are:
To follow this guide, you need:
One or more machines running a deb/rpm-compatible Linux OS; for example: Ubuntu or CentOS.
2 GiB or more of RAM per machine--any less leaves little room for your apps.
At least 2 CPUs on the machine that you use as a control-plane node.
Full network connectivity among all machines in the cluster. You can use either a public or a private network.
OP's VM had set RAM to 2GB which casued performance issue using different applications.
When RAM on the VM was set to 4GB, Virtual Machine is working perfectly fine.
I am trying to create Kubernetes cluster with different number of nodes using same machine. Here I want to create separate VMs and need to create node in those VMs. I am currently exploring about kubeadm and minikube for these tasks.
When I am exploring I had the following confusions:
I need to create 4 number of nodes each need to create in different VMs. Can I use kubeadm for these requirement?
Also found that Minikube is using for creating the single node structure and also possible to use to creation of VMs. What is the difference between kubeadm and minikube ?
If I want to create nodes in different VMs which tool should use along with installation of Kubernetes cluster master?
If I am using VMs, then can I directly install VMware workstation / virtualbox in my Ubuntu 16.04 ?
In AWS EC2, they already giving the Ubuntu as a virtual machine. So is possible to install VMware workstation on ubuntu? Since it is VMs on another VM.
Kubeadm should be a good choice for you. It is quite easy to use by just following the documentation. Minikube would give you only single node Kubernetes. As of minikube 1.10.1, it is possible to use multi-node clusters.
Kubeadm is a tool to get Kubernetes up and running on already existing machine. It will basically configure and start all required Kubernetes components (for minimum viable cluster). Kubeadm is the right tool to bootstrap the Kubernetes cluster on your virtual machines. But you need to prepare the machines your self (install OS + required software, networking, ...). kubeadm will not do it for you.
Minikube is a tool which will allow you to start locally single node Kubernetes cluster. This is usually done in a VM - minikube supports VirtualBox KVM and others. It will start for you the virtual machine and take care of everything. But it will not do a 4 node cluster for you.
Kubeadm takes care of both. You first setup the master and then use kubeadm on the worker nodes to join the master.
When you use Kubeadm, it doesn't really care what do you use for the virtualization. You can choose whatever you want.
Why do you want to run virtual machines on top of your EC2 machine? Why not just create more (perhaps smaller) EC2 machines for the cluster? You can use this as an inspiration: https://github.com/scholzj/terraform-aws-kubernetes. There are also some more advanced tools for setting up the whole cluster such as (for example) Kops.
We are running all our applications in Linux VM's and tried Kubernetes cluster on local Mac using minikube and it looks promising.
Interested in setting up Kubernetes on Linux VM's, but:
Is is possible to setup production ready cluster on Linux VM's?
As shown in kubernetes/kubeadm issue 465, setting up a cluster using VMs can be a challenge.
Using Calico will help, since it provides secure network connectivity for containers and virtual machine workloads.
Use Calico 2.6.
I was looking at this url.
It says-"If you already have a way to configure hosting resources, use kubeadm to easily bring up a cluster with a single command per machine."
What do you mean by "If you already have a way to configure hosting resources"?
If I have a few Ubuntu machines within my office LAN can I setup Kubernetes cluster on them using kubeadm?
It just means that you already have a way of installing an OS on these machines, booting them, assigning IPs on your LAN and so. If you can SSH into your nodes to be you are ready!
Follow the guide carefully and you will have a demo cluster in no time.
I have been looking at available Kubernetes storage add-ons and have been unable to put together something that would work with our setup. Current situation is several nodes each with an FC HBA controller connected to a single LUN. I realize that some sort of cluster FS will need to be implemented, but once that is in place I don't see how I would then connect this to Kubernetes.
We've discussed taking what we have and making an iSCSI or NFS host but in addition to requiring another dedicated machine, we lose all the advantages of having the storage directly available on each node. Is there any way to make use of our current infrastructure?
Details:
4x Kubernetes nodes (1 master) deployed via kubeadm on Ubuntu 16.04 using flannel as the network addon, each system has the SAN available as block device (/dev/sdb)