ansible-kubernetes-stolon

DEPRECATED! This is because stolon project is no longer maintained by the owners. Switched to CrunchyData PGO instead.

Ansible role and sample playbook to deploy sorintlab/stolon on a Kubernetes cluster.

Based on sorintlab/stolon/examples/kubernetes.

Prerequisites

1. Python3 and pip3
2. Developed and tested with ansible 2.8
3. Mitogen is higly recommended:

• Download: mkdir -p plugins && cd plugins && git clone https://github.com/dw/mitogen.git
• Set in sample-absible.cfg:
  • strategy_plugins = plugins/mitogen/ansible_mitogen/plugins/strategy
  • strategy = mitogen_linear

4. Setup ansible inventory:
   • To run remotely:
     • Set your ansible_host in inventory/host_vars/master to point to your kubernetes master
     • Set up your ssh key for authentication to the master
   • To run locally:
     • in inventory/host_vars/master, uncomment: ansible_connection: local
     • set the playbook variable kubeconfig_file_path pointing to a local kubeconfig

Run

• Full playbook:

  ANSIBLE_SSH_PIPELINING=true \
  ANSIBLE_CONFIG=sample-ansible.cfg \
  ansible-playbook sample-playbook.yml \
      --inventory sample-inventory \
      --extra-vars "@params-override.yml -v"

• Just database creation: add --tags data_clusters

• Just simple schema creation: add --tags create_schemas

• Just SQL scripts: add --tags execute_sql

Role parameters

Parameter	Default Value	Description
kubeconfig_file_path	undefined	Optional path to kubeconfig file containing k8s cluster, user and context. The one in a default location will be used if empty
kubernetes_retries	10	k8s objects: Maximum number of retries before giving up in error and drama
kubernetes_delay	15	k8s objects: Delay in seconds between retries
kubernetes_force	false	k8s objects: Replace the existing object instead of updating it
kubernetes_state	undefined	k8s objects: If set to 'absent' will delete all stolon k8s objects, but the data should be left intact
stolon_namespace	stolon	Kubernetes namespace
stolon_release	''	Optional prefix for stolon objetcs
stolon_rbac	true	Enable RBAC
stolon_cluster	kube-stolon	Stolon cluster name. Will be prefixed with stolon_release-
stolon_keeper_replicas	2	Number of keeper (statefulset) replicas
stolon_proxy_replicas	2	Number of proxy (deployment) replicas
stolon_sentinel_replicas	2	Number of sentinel (deployment) replicas
stolon_image	sorintlab/stolon:master-pg12	Docker image for all stolon components
stolon_secret_password	generated	Password for stolon database user. If not specified, a 15 length random password will be generated. Must NOT be base64 encoded
stolon_secret_replpassword	generated	Password for the replication user. If not specified, a 15 length random password will be generated. Must NOT be base64 encoded
stolon_stkeeper_debug	false	Enable debug for keeper
stolon_stproxy_debug	false	Enable debug for proxy
stolon_stsentinel_debug	false	Enable debug for sentinel
stolon_storage_class	stolon-local-storage	Name of k8s storage class to be created/used
stolon_storage_class_reclaim_policy	Retain	Reclaim policy, overriding k8s default of Delete
stolon_storage_size	1Gi	Size of the local PersistentVolume
stolon_storage_local_path	/stolon-local-data	Data directory. PostgreSQL data will be in stolon_storage_local_path/postgres
stolon_proxy_service.externalIPs	undefined	Array of IPs for exposing proxy-service
stolon_proxy_service.port	5432	External proxy port
stolonctl_retries	10	Number of retries for the stolonctl task before giving up. Increase this if hardware is slower
stolonctl_delay	15	Delay in seconds between each retry
postgresql_schemas	[]	List of objects to create roles with login and password and schemas
postgresql_scripts	[]	List of SQL statements to run after database creation (e.g. DDL to create schemas, etc)

Samples

The following can be set in a vars file, e.g. params-override.yml

1. External IPs for the proxy service:

   stolon_proxy_service:
     externalIPs:
     - 10.11.12.13

2. Create roles and schemas for applications

   ## Automatically create schemas and roles (accounts) to login to the schemas for various apps
   postgresql_schemas:
   ## Create a schema keycloak, and set role and password the same:
   - name: "keycloak"
   ## Create a schema with a different role and password
   - name: "myschema"
     role: "myrole"
     password: "mypassword"

3. SQl Scripts:

   postgresql_scripts:
   - |
     SOME OTHER SQL SCRIPT HERE;