Patroni Infoblox DNS integration

This software enables the setup of a master database service DNS entry in Infoblox network services for databases managed by Patroni. The hostname will be redirected to the current master any time a failover or switchover happens.

Installation

The package can be installed with Python's pip package manager:

pip install .

Only external dependency is on infoblox-client, the official Python client provided by Infoblox.

Setup

Make sure when Patroni is started with the following environment variables set. When using SystemD to start Patroni a good place to set them would be from an EnvironmentFile referenced from the SystemD patroni.service used to start Patroni.

WAPI_HOSTNAME="10.2.3.4" # Address where WAPI REST services can be accessed
WAPI_USER="foo"          # User to authenticate to WAPI with
WAPI_PASSWORD="bar"      # Password for authentication
# Template for hostname. {cluster} will get replaced by cluster name from Patroni (scope)
DATABASE_MASTER_HOSTNAME_TEMPLATE="master.{cluster}.dbs.example.com"

In Patroni configuration add the following lines to enable the callback to be called.

postgresql:
    callbacks:
        on_restart: infoblox-callback.py 
        on_role_change: infoblox-callback.py
        on_start: infoblox-callback.py
        on_stop: infoblox-callback.py

If using environment variables is not desired for some reason, the parameters can also be passed through Patroni configuration file:

postgresql:
    callbacks:
        on_restart: infoblox-callback.py -H 10.2.3.4 -u foo -p bar -4 master.{cluster}.dbs.example.com 
        on_role_change: infoblox-callback.py -H 10.2.3.4 -u foo -p bar -4 master.{cluster}.dbs.example.com
        on_start: infoblox-callback.py -H 10.2.3.4 -u foo -p bar -4 master.{cluster}.dbs.example.com
        on_stop: infoblox-callback.py -H 10.2.3.4 -u foo -p bar -4 master.{cluster}.dbs.example.com

This config will create and/or update an ARecord in DNS view called default. If a different DNS view needs to be used it can be specified with WAPI_DNS_VIEW.

Options

Environment variable	Command line parameter	Required	Description
DATABASE_MASTER_HOSTNAME_TEMPLATE	-4 --arecord	Y	Hostname to create. A {cluster} placeholder will be replaced with cluster name (scope) from Patroni.
	-i --ip	N	IP address that the hostname should point to when this host is master. Default is automatically detected from network interfaces.
WAPI_HOST	-H --host	Y	WAPI REST API endpoint hostname or IP
WAPI_USER	-u --username	Y	WAPI username for authentication
WAPI_PASSWORD	-p --password	Y	WAPI password for authentication
WAPI_INSECURE	-k --insecure	N	Validate WAPI certificates
WAPI_DNS_VIEW	-v --dns-view	N	WAPI DNS view where the hostname is created
WAPI_COMMENT	--comment	N	Comment to set on the created hostname. {cluster} will be replaces with cluster name (scope) from Patroni.
WAPI_VERSION	--wapi-version	N	WAPI API version to access.
	--debug	N	Extra logging for debugging