I'm wondering how can install a package inside the minikube VM. I need some tools.
I have tried the /bin/toolbox container, but It does not have internet conexion.
[root#docker-fedora-24 ~]# dnf update --verbose
cachedir: /var/cache/dnf
DNF version: 1.1.9
Cannot download 'https://mirrors.fedoraproject.org/metalink?repo=updates-released-f24&arch=x86_64': Cannot prepare internal mirrorlist: Curl error (6): Couldn't resolve host name for https://mirrors.fedoraproject.org/metalink?repo=updates-released-f24&arch=x86_64 [Could not resolve host: mirrors.fedoraproject.org].
Error: Failed to synchronize cache for repo 'updates'
I have tried the same toolbox script in my computer and it is properly working.
What configuration parameters I'm missing in minikube or systemd-nspaw?
Or how can I cook a customized minikube VM?
Thanks a lot
You can run minicube without VM on your local docker (if you use linux):
minikube start --vm-driver=none
A alternative, run toolbox with docker run --net=host ... to make network for container more transparent. Troubleshoot your internet connection with nslookup, traceroute/tracepath, curl -v, ifconfig.
http://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:Ch04:_Simple_Network_Troubleshooting#.WfY1xGi0OUk
Minikube is not meant to be tweaked. The advised method is to prepare a helm chart for your application. As part of the helm chart you can add whatever tool you need in your docker file... Including make... Then you can install or upgrade your package in kubernetes/minikube using helm.
I had a similar problem when I wanted to use tcpdump in the minikube VM.
I ended up using minikube mount SRC-dir:DST-dir to mount the host folder inside the VM and copying the tcpdump binary along with dependent libs (libcrypto and libpcap) to the mount point.
Then I executed tcpdump from the minikube VM and it worked.
Note: My host arch and the minikube VM arch (x86_64) was the same.
Note also: export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:DST-dir has to be done.
Related
I am running a local Kubernetes cluster through Docker Desktop on Windows. I'm attempting to modify my kube-apiserver config, and all of the information I've found has said to modify /etc/kubernetes/manifests/kube-apiserver.yaml on the master. I haven't been able to find this file, and am not sure what the proper way is to do this. Is there a different process because the cluster is through Docker Desktop?
Is there a different process because the cluster is through Docker Desktop?
You can get access to the kubeapi-server.yaml with a Kubernetes that is running on Docker Desktop but in a "hacky" way. I've included the explanation below.
For setups that require such reconfigurations, I encourage you to use different solution like for example minikube.
Minikube has a feature that allows you to pass the additional options for the Kubernetes components. You can read more about --extra-config ExtraOption by following this documentation:
Minikube.sigs.k8s.io: Docs: Commands: Start
As for the reconfiguration of kube-apiserver.yaml with Docker Desktop
You need to run following command:
docker run -it --privileged --pid=host debian nsenter -t 1 -m -u -n -i sh
Above command will allow you to run:
vi /etc/kubernetes/manifests/kube-apiserver.yaml
This lets you edit the API server configuration. The Pod running kubeapi-server will be restarted with new parameters.
You can check below StackOverflow answers for more reference:
Stackoverflow.com: Answer: Where are the Docker Desktop for Windows kubelet logs located?
Stackoverflow.com: Answer: How to change the default nodeport range on Mac (docker-desktop)?
I've used this answer without $ screen command and I was able to reconfigure kubeapi-server on Docker Desktop in Windows
I am exploring and learning about containers and kubernetes using podman and minikube on a linux workstation. I use podman to build images on the workstation and would like to deploy these images in minikube also running on the workstation using the kvm2 virtual machine driver. I also start minikube using the CRI-O container runtime.
What are efficient workflows to deploy these images from the workstation to minikube in this scenario? Docker is not running on the minikube VM so the reusing the Docker daemon as described in the minikube documentation is not an option. Sharing the host file system with minikube also appears to not be viable at this time when using kvm2.
Is running a local registry that is visible to both the workstation and the minikube vm the best option? Answers to How to use local docker images with Minikube? and (Kubernetes + Minikube) can't get docker image from local registry appear to offer good solutions for configuring a local registry.
Would skopeo be a solution?
Edit: this is a nice post describing how to set up a registry using podman: https://computingforgeeks.com/create-docker-container-registry-with-podman-letsencrypt/
thank you
Brad
Minikube documentation provides the foundation for a potential workflow at https://minikube.sigs.k8s.io/docs/tasks/docker_registry/. In order to use podman in lieu of docker I did the following
Start minikube, as instructed, with the --insecure-registry flag. I specifically use
minikube start --network-plugin=cni --enable-default-cni --bootstrapper=kubeadm --container-runtime=cri-o --cpus 4 --memory 4g --insecure-registry "192.168.39.0/24"
Enable the minikube registry addon.
minikube addons enable registry
Configure podman to use the insecure minikube registry by adding the registry to the insecure registries section of /etc/containers/registries.conf. This section now looks like
[registries.insecure]
registries = ['192.168.39.175:5000']
where 192.168.39.175 is the minikube ip. This ip may change following minikube restarts.
Follow the build, push and run commands in https://minikube.sigs.k8s.io/docs/tasks/docker_registry/ substituting podman for docker. This assumes the test-img container file exists.
Build: podman build --tag $(minikube ip):5000/test-img .
Push: podman push $(minikube ip):5000/test-img
Run: kubectl run test-img --image=$(minikube ip):5000/test-img
This worked but suffers from a serious complication: there is no apparent way at this time to set the IP address for the minikube VM when using kvm2. The IP will always be in the 192.168.39.0/24 subnet but that is the only certainty. Each time minikube is started the IP address of the registry will change which has significant implications for podman and the workflow in general.
More to come an another solution.
I am looking to execute
apt install tcpdump
but facing permission denial, upon looking to set the directory to root, it is asking me for password and I don't know from where to get that password.
I installed nginx helm chart from stable/nginx repository with no RBAC
Please see snapshot for details on error, while I tried installing tcpdump in the pod after doing ssh into it.
In Using GDB with Nginx, you can find troubleshooting section:
Shortly:
find the node where your pod is running (kubectl get pods -o wide)
ssh into the node
find the docker_ID for this image (docker ps | grep pod_name)
run docker exec -it --user=0 --privileged docker_ID bash
Note: Runtime privilege and Linux capabilities
When the operator executes docker run --privileged, Docker will enable access to all devices on the host as well as set some configuration in AppArmor or SELinux to allow the container nearly all the same access to the host as processes running outside containers on the host. Additional information about running with --privileged is available on the Docker Blog.
Additional resources:
ROOT IN CONTAINER, ROOT ON HOST
Hope this help.
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
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