Microk8s on LXD

Kubernetes Cluster in less than 15 minutes on Ubuntu

• https://medium.com/@ridwanfajar/getting-started-with-microk8s-up-and-running-kubernetes-locally-310640dae156
• https://linuxcontainers.org/lxd/getting-started-cli/
• https://microk8s.io/docs/lxd

Begin with a simple Ubuntu 20.04 host with LXD installed: snap install lxd - https://linuxcontainers.org/lxd/getting-started-cli/

lxc profile create microk8s
wget https://raw.githubusercontent.com/ubuntu/microk8s/master/tests/lxc/microk8s-zfs.profile -O microk8s.profile
cat microk8s.profile | lxc profile edit microk8s
lxc launch -p default -p microk8s ubuntu:20.04 h1
lxc launch -p default -p microk8s ubuntu:20.04 h2
lxc launch -p default -p microk8s ubuntu:20.04 h3

h1

lxc exec h1 /bin/bash
snap install microk8s --classic --channel=1.19/stable
microk8s status
microk8s add-node

h2

snap install microk8s --classic --channel=1.19/stable
microk8s join 10.28.99.198:25000/<output from existing node microk8s add-node>

h3

snap install microk8s --classic --channel=1.19/stable
microk8s join 10.28.99.198:25000/<output from existing node microk8s add-node>

Enable dash on h1

microk8s enable dashboard
token=$(microk8s kubectl -n kube-system get secret | grep default-token | cut -d " " -f1)
microk8s kubectl -n kube-system describe secret $token
microk8s kubectl port-forward -n kube-system service/kubernetes-dashboard 11443:443

lxc config device add h1 tcp33443 proxy listen=tcp:0.0.0.0:33443 connect=tcp:127.0.0.1:11443

browse to https://mylxdhostfromcmdabove:33443/

Namespace Getters in kubernetes

• https://kubernetes.io/docs/reference/kubectl/cheatsheet/#viewing-finding-resources
• https://microk8s.io/docs

# alias kubectl='microk8s kubectl'
microk8s kubectl get all
microk8s kubectl get nodes
microk8s kubectl get services
microk8s kubectl get pods

Other

• https://kubernetes.io/docs/reference/kubectl/cheatsheet/#viewing-finding-resources

LXD issues with app armour

https://blog.sleeplessbeastie.eu/2020/07/20/how-to-deal-with-missing-apparmor-profiles-for-microk8s-on-lxd/

Run on all k8s nodes

aa-status
apparmor_parser --add /var/lib/snapd/apparmor/profiles/snap.microk8s.*

micro-k8s status
micro-k8s add-node

NFS Server

nfs server centos 8 with hostname nas in dns

sudo dnf install nfs-utils
systemctl enable --now nfs-server
systemctl status nfs-server

/etc/exports

/kub/default-storage    *(rw,sync,no_subtree_check,insecure,no_root_squash)
# var/nfs 10.x.x.x/32(rw,sync,no_subtree_check,insecure) 10.x.x.x/32(rw,sync,no_subtree_check,insecure) 10.x.x.x/32(rw,sync,no_subtree_check,insecure)
# /nas/share    *(rw,sync,no_subtree_check,insecure)

NFS Clients on Each Kubernetes Node

Make default storage class (hostpath) an nfs hostpath

sudo apt install -y nfs-client
mkdir /var/snap/microk8s/common/default-storage
echo "nas:/kub/default-storage  /var/snap/microk8s/common/default-storage  nfs" >> /etc/fstab
mount -a
microk8s stop && microk8s start

Refs

• https://microk8s.io/high-availability
• https://microk8s.io/docs/clustering
• https://microk8s.io/docs/addon-dashboard
• https://blog.getambassador.io/explore-the-ambassador-api-gateway-with-microk8s-f75a7a295113#:~:text=With%20MicroK8s%20v1.,a%20great%20fit%20for%20MicroK8s.&text=Ambassador%20is%20now%20ready%20for,Controller%20in%20your%20local%20cluster.
• https://www.getambassador.io/docs/latest/topics/running/running/
• https://kubernetes.io/docs/tutorials/stateless-application/expose-external-ip-address/