135 lines
No EOL
5.3 KiB
Markdown
135 lines
No EOL
5.3 KiB
Markdown
Ansible variables
|
|
===============
|
|
|
|
|
|
Inventory
|
|
-------------
|
|
The inventory is composed of 3 groups:
|
|
|
|
* **kube-node** : list of kubernetes nodes where the pods will run.
|
|
* **kube-master** : list of servers where kubernetes master components (apiserver, scheduler, controller) will run.
|
|
Note: if you want the server to act both as master and node the server must be defined on both groups _kube-master_ and _kube-node_
|
|
* **etcd**: list of server to compose the etcd server. you should have at least 3 servers for failover purposes.
|
|
|
|
Below is a complete inventory example:
|
|
|
|
```
|
|
## Configure 'ip' variable to bind kubernetes services on a
|
|
## different ip than the default iface
|
|
node1 ansible_ssh_host=95.54.0.12 # ip=10.3.0.1
|
|
node2 ansible_ssh_host=95.54.0.13 # ip=10.3.0.2
|
|
node3 ansible_ssh_host=95.54.0.14 # ip=10.3.0.3
|
|
node4 ansible_ssh_host=95.54.0.15 # ip=10.3.0.4
|
|
node5 ansible_ssh_host=95.54.0.16 # ip=10.3.0.5
|
|
node6 ansible_ssh_host=95.54.0.17 # ip=10.3.0.6
|
|
|
|
[kube-master]
|
|
node1
|
|
node2
|
|
|
|
[etcd]
|
|
node1
|
|
node2
|
|
node3
|
|
|
|
[kube-node]
|
|
node2
|
|
node3
|
|
node4
|
|
node5
|
|
node6
|
|
|
|
[k8s-cluster:children]
|
|
kube-node
|
|
kube-master
|
|
etcd
|
|
```
|
|
|
|
Group vars
|
|
--------------
|
|
The main variables to change are located in the directory ```inventory/group_vars/all.yml```.
|
|
|
|
Ansible tags
|
|
------------
|
|
The following tags are defined in playbooks:
|
|
|
|
| Tag name | Used for
|
|
|--------------------------|---------
|
|
| apps | K8s apps definitions
|
|
| azure | Cloud-provider Azure
|
|
| bootstrap-os | Anything related to host OS configuration
|
|
| calico | Network plugin Calico
|
|
| canal | Network plugin Canal
|
|
| cloud-provider | Cloud-provider related tasks
|
|
| dnsmasq | Configuring DNS stack for hosts and K8s apps
|
|
| docker | Configuring docker for hosts
|
|
| download | Fetching container images to a delegate host
|
|
| etcd | Configuring etcd cluster
|
|
| etcd-pre-upgrade | Upgrading etcd cluster
|
|
| etcd-secrets | Configuring etcd certs/keys
|
|
| etchosts | Configuring /etc/hosts entries for hosts
|
|
| facts | Gathering facts and misc check results
|
|
| flannel | Network plugin flannel
|
|
| gce | Cloud-provider GCP
|
|
| hyperkube | Manipulations with K8s hyperkube image
|
|
| k8s-pre-upgrade | Upgrading K8s cluster
|
|
| k8s-secrets | Configuring K8s certs/keys
|
|
| kpm | Installing K8s apps definitions with KPM
|
|
| kube-apiserver | Configuring self-hosted kube-apiserver
|
|
| kube-controller-manager | Configuring self-hosted kube-controller-manager
|
|
| kubectl | Installing kubectl and bash completion
|
|
| kubelet | Configuring kubelet service
|
|
| kube-proxy | Configuring self-hosted kube-proxy
|
|
| kube-scheduler | Configuring self-hosted kube-scheduler
|
|
| localhost | Special steps for the localhost (ansible runner)
|
|
| master | Configuring K8s master node role
|
|
| netchecker | Installing netchecker K8s app
|
|
| network | Configuring networking plugins for K8s
|
|
| nginx | Configuring LB for kube-apiserver instances
|
|
| node | Configuring K8s minion (compute) node role
|
|
| openstack | Cloud-provider OpenStack
|
|
| preinstall | Preliminary configuration steps
|
|
| resolvconf | Configuring /etc/resolv.conf for hosts/apps
|
|
| upgrade | Upgrading, f.e. container images/binaries
|
|
| upload | Distributing images/binaries across hosts
|
|
| weave | Network plugin Weave
|
|
|
|
Note: Use the ``bash scripts/gen_tags.sh`` command to generate a list of all
|
|
tags found in the codebase. New tags will be listed with the empty "Used for"
|
|
field.
|
|
|
|
Example commands
|
|
----------------
|
|
Example command to filter and apply only DNS configuration tasks and skip
|
|
everything else related to host OS configuration and downloading images of containers:
|
|
|
|
```
|
|
ansible-playbook -i inventory/inventory.ini cluster.yml --tags preinstall,dnsmasq,facts --skip-tags=download,bootstrap-os
|
|
```
|
|
And this play only removes the K8s cluster DNS resolver IP from hosts' /etc/resolv.conf files:
|
|
```
|
|
ansible-playbook -i inventory/inventory.ini -e dns_server='' cluster.yml --tags resolvconf
|
|
```
|
|
And this prepares all container images localy (at the ansible runner node) without installing
|
|
or upgrading related stuff or trying to upload container to K8s cluster nodes:
|
|
```
|
|
ansible-playbook -i inventory/inventory.ini cluster.yaml \
|
|
-e download_run_once=true -e download_localhost=true \
|
|
--tags download --skip-tags upload,upgrade
|
|
```
|
|
|
|
Note: use `--tags` and `--skip-tags` wise and only if you're 100% sure what you're doing.
|
|
|
|
Bastion host
|
|
--------------
|
|
If you prefer to not make your nodes publicly accessible (nodes with private IPs only),
|
|
you can use a so called *bastion* host to connect to your nodes. To specify and use a bastion,
|
|
simply add a line to your inventory, where you have to replace x.x.x.x with the public IP of the
|
|
bastion host.
|
|
|
|
```
|
|
bastion ansible_ssh_host=x.x.x.x
|
|
```
|
|
|
|
For more information about Ansible and bastion hosts, read
|
|
[Running Ansible Through an SSH Bastion Host](http://blog.scottlowe.org/2015/12/24/running-ansible-through-ssh-bastion-host/) |