Can't Install Kubernetes on Ubuntu 16.04 - kubernetes

I have tried to install Kubernetes on 3 separate Ubuntu 16.04 machines, with poor results. On all three machines, the recommended installation, using snap and conjure-up did not work:
gknight#pz1:~$ sudo snap install conjure-up --classic
[sudo] password for gknight:
gknight#pz1:~$ sudo reboot
gknight#pz1:~$ conjure-up kubernetes
dropping privs did not work
This is the snap version:
gknight#pz1:~$ snap --version
snap 2.33.1ubuntu2
snapd 2.33.1ubuntu2
series 16
ubuntu 16.04
kernel 4.4.0-130-generic
On two, local, machines, the repository method worked:
sudo curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add
add the following to sources.list.d, as kubernetes.list:
deb http://apt.kubernetes.io/ kubernetes-xenial main
apt-get update
apt-get install -y kubelet kubeadm kubectl kubernetes-cni
But, on a remote 512mb KVM VPS (PnZ Hosting), although Docker installs and runs just fine, when I install kubelet, etc. and do nothing else, it soon runs the uptime load average up to 12 or so, and I can barely get through to it to reboot. There are no obvious error messages (and swap is turned off).
So, does the "conjure-up" method work on any Ubuntu 16.04 today?
What is Kubernetes doing that's taking over the KVM machine?
Finally, is there any other way to install Kubernetes?

remote 512mb KVM VPS
That's almost certainly the problem, as I don't know of very much software nowadays that will run in that little memory. It matches your experience that the machine will start swapping like mad, driving the I/O pressure through the roof

Agree with #Matthew & #Michael - 512mb is not enough to run Kubernetes.
Increase your memory up to 1GB min and retry.
Apiserver and etcd together are fine on a machine with 1 core and 1GB
RAM for clusters with 10s of nodes.
You can read more documentation here.
Conjure method works fine for me using this instruction.
Ubuntu version:
Distributor ID: Ubuntu
Description: Ubuntu 16.04.4 LTS
Release: 16.04
Ways to install Kubernetes:
Local Kubernetes development with LXD
Running Kubernetes Locally via Minikube
Using kubeadm
Use prepared cloud solutions, for example Google Kubernetes Engine, Amazon EKS or many many others.

Related

Can I install minikube on ubuntu without virtualBox?

I want to start practicing with k8s for the CKAD exam. I run on ubuntu 18.04.
I noticed everywhere that I need to download Virtualbox for minikube. I believe that VB is needed in case I don't start my cluster with a driver but if I use the Docker driver when I start my cluster shouldn't that be enough? Is microk8s a better option?
It seems that the preferred way is use --driver=docker driver instead of --driver=none for minikube, although it is technically not baremetal as it is significantly easier to configure and does not require root access. The ‘none’ driver is recommended for advanced users only. (info below from https://minikube.sigs.k8s.io/docs/drivers/docker/)
docker
Overview
The Docker driver allows you to install Kubernetes into an existing Docker install. On Linux, this does not require virtualization to be enabled.
Requirements
Install Docker 18.09 or higher
amd64 or arm64 system.
Usage
Start a cluster using the docker driver:
minikube start --driver=docker
To make docker the default driver:
minikube config set driver docker
Yes you can. Check here.
Minikube also supports a --driver=none option that runs the Kubernetes components on the host and not in a VM. Using this driver requires Docker and a Linux environment but not a hypervisor.
Jus run
$ minikube start
Caution: If you use the none driver, some Kubernetes components run as privileged containers that have side effects outside of the Minikube environment. Those side effects mean that the none driver is not recommended for personal workstations

Error Starting Minikube on Ubuntu VM VirutalBox

I do have an Ubuntu VM in VirtualBox on Windows 10. If i follow the instructions to install Minikube I get a start error:
> minikube start &
[1] 4297
vagrant#ubuntu-xenial:~$ o minikube v0.35.0 on linux (amd64)
> Creating virtualbox VM (CPUs=2, Memory=2048MB, Disk=20000MB) ...
# Downloading Minikube ISO ...
184.42 MB / 184.42 MB [============================================] 100.00%
0s
! Unable to start VM: create: precreate: VBoxManage not found. Make sure
VirtualBox is installed and VBoxManage is in the path
Does it mean i need to install VirtualBox in the Ubuntu VM too? Kind of VB inside VB..
thanks
I'd recommend to install Minikube on your host OS (Windows) and use the already installed Virtual box as a hypervisor provider.
If for any reason you want to launch it on Ubuntu VM, there are two options:
I. Minikube supports a --vm-driver=none option that runs the Kubernetes components on the host and not in a VM. Using this driver requires Docker and a Linux environment, but not a hypervisor. In this case you have to provide an address to you local API server
`minikube start --vm-driver=none --apiserver-ips 127.0.0.1 --apiserver-name localhost`
And then go and edit ~/.kube/config, replacing the server IP that was
detected from the main network interface with "localhost". For example:
apiVersion: v1
clusters:
- cluster:
certificate-authority-data:/home/asuh/.minikube/ca.crt
server: https://localhost:8443
name: minikube
II. Install VM Ware on Windows and run Ubuntu within installed Virtualbox
and and enabled VT-X/AMD-v in outer VM.
Regarding the error you have at the moment:
However now i get another error like: /usr/local/bin/minikube: cannot
execute binary file
Make sure you have installed a proper version of Minikube. For your Ubuntu VM it should be
curl -Lo minikube https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64 \
&& chmod +x minikube
It is not recommended to use VM inside VM to run minikube. Check this answer. Try to run minikube with no vm drivers.
minikube start --vm-driver=none
I have read on minikube issues, but can not find it right now.
HTH

503 Service Temporarily Unavailable nginx/1.13.9 in jenkins x

I have created kubernetes cluster using minikube and installed Jenkins x on it.
I am not able to access the Jenkins x dashboard.
Error 503 Service Temporarily Unavailable nginx/1.13.9.
note: I have tried with restarting minikube cluster also.
As mentioned by James Rawlings in the comments, it's likely to be a resource issue. The recommendations in the manual are:
A known good configuration on a 2015 model Macbook Pro is to use 8 GB of RAM, 8 cores, a 150 GB disk size and hyperkit.
The disk size is particularly large as a number of images will need to be downloaded.
So we highly recommend using one of the public clouds above to try out Jenkins X. They all have free tiers so it should not cost you any significant cash and it’ll give you a chance to try out the cloud.
Default minikube installation uses only 2048 MB of RAM, 2 CPU cores and 20Gb disk space. You can adjust minikube VM size using command line options:
$ minikube start --cpus=8 --memory=8192 --disk-size=150g --vm-driver=hyperkit
or use jx tool for that:
For MacOS
$ brew install docker-machine-driver-hyperkit
# docker-machine-driver-hyperkit need root owner and uid
$ sudo chown root:wheel /usr/local/opt/docker-machine-driver-hyperkit/bin/docker-machine-driver-hyperkit
$ sudo chmod u+s /usr/local/opt/docker-machine-driver-hyperkit/bin/docker-machine-driver-hyperkit
$ brew tap jenkins-x/jx
$ brew install jx
$ jx create cluster minikube
For linux:
$ curl -L https://github.com/jenkins-x/jx/releases/download/v1.3.784/jx-linux-amd64.tar.gz | tar xzv
$ sudo mv jx /usr/local/bin
$ jx create cluster minikube

Unable to bootstrap (cloud type: localhost) - Error when installing Kuberneters cluster locally with LXD/Conjure-up

Using Ubuntu 18.04.
I am trying to install a kubernetes cluster on my local machine (localhost) using this guide (LXD + conjure-up kubernetes):
https://kubernetes.io/docs/getting-started-guides/ubuntu/local/#before-you-begin
When I run:
conjure-up kubernetes
I select the following installation:
and select localhost for "Choose a cloud" and use the defaults for the rest of the install wizard. It then starts to install and after 30-40 minutes it completes with this error:
Here is the log:
https://pastebin.com/raw/re1UvrUU
Where one error says:
2018-07-25 20:09:38,125 [ERROR] conjure-up/canonical-kubernetes - events.py:161 - Unhandled exception in <Task finished coro=<BaseBootstrapController.run() done, defined at /snap/conjure-up/1015/lib/python3.6/site-packages/conjureup/controllers/juju/bootstrap/common.py:15> exception=BootstrapError('Unable to bootstrap (cloud type: localhost)',)>
but that does not really help much.
Any suggestion to why the install wizard/conjure-up fails?
Also based on this post:
https://github.com/conjure-up/conjure-up/issues/1308
I have tried to first disable firewall:
sudo ufw disable
and then re-run installation/conjure install wizard. But I get the same error.
Some more details on how I installed and configured LXD/conjure-up below:
$ snap install lxd
lxd 3.2 from 'canonical' installed
$ /snap/bin/lxd init
Would you like to use LXD clustering? (yes/no) [default=no]:
Do you want to configure a new storage pool? (yes/no) [default=yes]:
Name of the new storage pool [default=default]:
Name of the storage backend to use (btrfs, ceph, dir, lvm) [default=btrfs]:
Create a new BTRFS pool? (yes/no) [default=yes]:
Would you like to use an existing block device? (yes/no) [default=no]:
Size in GB of the new loop device (1GB minimum) [default=26GB]:
Would you like to connect to a MAAS server? (yes/no) [default=no]:
Would you like to create a new local network bridge? (yes/no) [default=yes]:
What should the new bridge be called? [default=lxdbr0]:
What IPv4 address should be used? (CIDR subnet notation, “auto” or “none”) [default=auto]:
What IPv6 address should be used? (CIDR subnet notation, “auto” or “none”) [default=auto]:
Would you like LXD to be available over the network? (yes/no) [default=no]:
Would you like stale cached images to be updated automatically? (yes/no) [default=yes]
Would you like a YAML "lxd init" preseed to be printed? (yes/no) [default=no]:
Configured group membership:
sudo usermod -a -G lxd $USER
newgrp lxd
Next installed:
sudo snap install conjure-up --classic
And then ran installation:
conjure-up kubernetes
I wasn't able to reproduce your exact problem but i got conjure-up + lxd installed and in the end Kubernetes on my newly installed VirtualBox Ubuntu 18.04 (Desktop) VM. Hopefully this answer could help you somehow!
I looked through the kubernetes.io documentation page and that one lacked tiny bits of information, it does mention lxd but not the part with lxd init which i assume you picked up in the conjure-up user manual.
So with that said, i followed the conjure-up user manual with some minor changes on the way. I'm assuming that it's OK for you to use the edge version of conjure-up, i started off with the stable one but changed to edge when testing different combinations.
Also please ensure that you have the recommended resources available stated by the user manual, conjure-up and the Canoncial Distribution of Kubernetes launches a number of containers for you. You might not need 3 x etcd, 3 x worker nodes and 2 x Master, and if you don't just tune the number of containers down in the conjure-up wizard.
These are the steps i performed (as my local user):
Make sure your Ubuntu box are updated: sudo apt update && sudo apt upgrade
Install conjure-up by running: sudo snap install conjure-up --classic --edge
Install lxd by running: sudo snap install lxd
With lxd comes the client part which is lxc, if you run e.g. lxc list you should get an empty table (no containers started yet). I got an permission error at this time, i ran the following: sudo chown -R lxd:lxd /var/snap/lxd/ to change owner and group of the lxd directory containing the socket you'll be communicating with using lxc.
Add your user to the lxdgroup: sudo usermod -a -G lxd $USER && newgrp lxd, log off and on to make this permanent and not only active in your current shell.
Now create a lxd bridge manually with the following command: lxc network create lxdbr1 ipv4.address=auto ipv4.nat=true ipv6.address=none ipv6.nat=false
Now let's run the init part of lxd with lxd init. Remember to answer no when being asked to create a new local network bridge?, in the next prompt provide your newly created network bridge instead (lxdbr1). The rest of the answers to the questions can be left as default.
Now continue with running conjure-up kubernetes and choose localhost as your type. For me the localhost choice was greyed out from the beginning, it worked when i created the network bridge manually and not via the lxd init step.
Skip the additional components you can install like Rancher, Prometheus etc.
Choose your new network bridge and the default storage pool, proceed to the next step.
In the next step customize your Kubernetes cluster if needed and then hit Deploy. And now you wait!
You can always troubleshoot and list all containers created with the lxc tool. If you've ever used Docker the lxc tool feels a lot like the docker client.
And finally some thoughts and observations, there's a lot of moving parts to conjure-up as you might have seen. It's actually described as: conjure-up is a thin layer spanning a few different underlying technologies - Juju, MAAS and LXD.
For reference, i ended up having the following versions installed:
lxd version 3.3
conjure-up version 2.6.1

Local Kubernetes on CentOS

I am trying to install Kubernetes locally on my CentOS. I am following this blog http://containertutorials.com/get_started_kubernetes/index.html, with appropriate changes to match CentOS and latest Kubernetes version.
./kube-up.sh script runs and exists with no errors and I don't see the server started on port 8080. Is there a way to know what was the error and if there is any other procedure to follow on CentOS 6.3
The easiest way to install the kubernetes cluster is using kubeadm. The initial post which details the steps of setup is here. And the detailed documentation for the kubeadm can be found here. With this you will get the latest released kubernetes.
If you really want to use the script to bring up the cluster, I did following:
Install the required packages
yum install -y git docker etcd
Start docker process
systemctl enable --now docker
Install golang
Latest go version because default centos golang is old and for kubernetes to compile we need at least go1.7
curl -O https://storage.googleapis.com/golang/go1.8.1.linux-amd64.tar.gz
tar -C /usr/local -xzf go1.8.1.linux-amd64.tar.gz
export PATH=$PATH:/usr/local/go/bin
Setup GOPATH
export GOPATH=~/go
export GOBIN=$GOPATH/bin
export PATH=$PATH:$GOBIN
Download k8s source and other golang dependencies
Note: this might take sometime depending on your internet speed
go get -d k8s.io/kubernetes
go get -u github.com/cloudflare/cfssl/cmd/...
Start cluster
cd $GOPATH/src/k8s.io/kubernetes
./hack/local-up-cluster.sh
In new terminal
alias kubectl=$GOPATH/src/k8s.io/kubernetes/cluster/kubectl.sh
kubectl get nodes