144 lines
4.5 KiB
ReStructuredText
144 lines
4.5 KiB
ReStructuredText
=====================
|
|
Gate-Based Kubernetes
|
|
=====================
|
|
|
|
Overview
|
|
========
|
|
|
|
You can use any Kubernetes deployment tool to bring up a working Kubernetes
|
|
cluster for use with OpenStack-Helm. This guide describes how to simply stand
|
|
up a multinode Kubernetes cluster via the OpenStack-Helm gate scripts,
|
|
which use KubeADM and Ansible. Although this cluster won't be
|
|
production-grade, it will serve as a quick starting point in a lab or
|
|
proof-of-concept environment.
|
|
|
|
OpenStack-Helm-Infra KubeADM deployment
|
|
=======================================
|
|
|
|
On the worker nodes:
|
|
|
|
.. code-block:: shell
|
|
|
|
#!/bin/bash
|
|
set -xe
|
|
sudo apt-get update
|
|
sudo apt-get install --no-install-recommends -y git
|
|
|
|
|
|
SSH-Key preparation
|
|
-------------------
|
|
|
|
Create an ssh-key on the master node, and add the public key to each node that
|
|
you intend to join the cluster.
|
|
|
|
.. note::
|
|
1. To generate the key you can use ``ssh-keygen -t rsa``
|
|
2. To copy the ssh key to each node, this can be accomplished with
|
|
the ``ssh-copy-id`` command, for example: *ssh-copy-id
|
|
ubuntu@192.168.122.178*
|
|
3. Copy the key: ``sudo cp ~/.ssh/id_rsa /etc/openstack-helm/deploy-key.pem``
|
|
4. Set correct ownership: ``sudo chown ubuntu
|
|
/etc/openstack-helm/deploy-key.pem``
|
|
|
|
Test this by ssh'ing to a node and then executing a command with
|
|
'sudo'. Neither operation should require a password.
|
|
|
|
Clone the OpenStack-Helm Repos
|
|
------------------------------
|
|
|
|
Once the host has been configured the repos containing the OpenStack-Helm charts
|
|
should be cloned onto each node in the cluster:
|
|
|
|
.. code-block:: shell
|
|
|
|
#!/bin/bash
|
|
set -xe
|
|
|
|
sudo chown -R ubuntu: /opt
|
|
git clone https://opendev.org/openstack/openstack-helm-infra.git /opt/openstack-helm-infra
|
|
git clone https://opendev.org/openstack/openstack-helm.git /opt/openstack-helm
|
|
|
|
|
|
Create an inventory file
|
|
------------------------
|
|
|
|
On the master node create an inventory file for the cluster:
|
|
|
|
.. note::
|
|
node_one, node_two and node_three below are all worker nodes,
|
|
children of the master node that the commands below are executed on.
|
|
|
|
.. code-block:: shell
|
|
|
|
#!/bin/bash
|
|
set -xe
|
|
cat > /opt/openstack-helm-infra/tools/gate/devel/multinode-inventory.yaml <<EOF
|
|
all:
|
|
children:
|
|
primary:
|
|
hosts:
|
|
node_one:
|
|
ansible_port: 22
|
|
ansible_host: $node_one_ip
|
|
ansible_user: ubuntu
|
|
ansible_ssh_private_key_file: /etc/openstack-helm/deploy-key.pem
|
|
ansible_ssh_extra_args: -o StrictHostKeyChecking=no
|
|
nodes:
|
|
hosts:
|
|
node_two:
|
|
ansible_port: 22
|
|
ansible_host: $node_two_ip
|
|
ansible_user: ubuntu
|
|
ansible_ssh_private_key_file: /etc/openstack-helm/deploy-key.pem
|
|
ansible_ssh_extra_args: -o StrictHostKeyChecking=no
|
|
node_three:
|
|
ansible_port: 22
|
|
ansible_host: $node_three_ip
|
|
ansible_user: ubuntu
|
|
ansible_ssh_private_key_file: /etc/openstack-helm/deploy-key.pem
|
|
ansible_ssh_extra_args: -o StrictHostKeyChecking=no
|
|
EOF
|
|
|
|
Create an environment file
|
|
--------------------------
|
|
|
|
On the master node create an environment file for the cluster:
|
|
|
|
.. code-block:: shell
|
|
|
|
#!/bin/bash
|
|
set -xe
|
|
function net_default_iface {
|
|
sudo ip -4 route list 0/0 | awk '{ print $5; exit }'
|
|
}
|
|
cat > /opt/openstack-helm-infra/tools/gate/devel/multinode-vars.yaml <<EOF
|
|
kubernetes_network_default_device: $(net_default_iface)
|
|
EOF
|
|
|
|
Additional configuration variables can be found `here
|
|
<https://github.com/openstack/openstack-helm-infra/blob/master/roles/deploy-kubeadm-aio-common/defaults/main.yml>`_.
|
|
In particular, ``kubernetes_cluster_pod_subnet`` can be used to override the
|
|
pod subnet set up by Calico (the default container SDN), if you have a
|
|
preexisting network that conflicts with the default pod subnet of 192.168.0.0/16.
|
|
|
|
.. note::
|
|
This installation, by default will use Google DNS servers, 8.8.8.8 or 8.8.4.4
|
|
and updates resolv.conf. These DNS nameserver entries can be changed by
|
|
updating file ``/opt/openstack-helm-infra/tools/images/kubeadm-aio/assets/opt/playbooks/vars.yaml``
|
|
under section ``external_dns_nameservers``. This change must be done on each
|
|
node in your cluster.
|
|
|
|
|
|
Run the playbooks
|
|
-----------------
|
|
|
|
On the master node run the playbooks:
|
|
|
|
.. code-block:: shell
|
|
|
|
#!/bin/bash
|
|
set -xe
|
|
cd /opt/openstack-helm-infra
|
|
make dev-deploy setup-host multinode
|
|
make dev-deploy k8s multinode
|