patroni/SETTINGS.rst

===========================
YAML Configuration Settings
===========================

Global/Universal
----------------
-  **loop\_wait**: the number of seconds the loop will sleep.
-  **ttl**: the TTL to acquire the leader lock. Think of it as the length of time before initiation of the automatic failover process.

Consul
------
-  **host**: the host:port for the Consul endpoint.
-  **scope**: the relative path used on Consul's HTTP API for this deployment; makes it possible to run multiple HA deployments from a single Consul cluster.
-  **ttl**: the TTL to acquire the leader lock. Think of it as the length of time before initiation of the automatic failover process.

etcd
----
-  **host**: the host:port for the etcd endpoint.
-  **scope**: the relative path used on etcd's HTTP API for this deployment. Makes it possible to run multiple HA deployments from a single etcd cluster.
-  **ttl**: the TTL to acquire the leader lock. Think of it as the length of time before initiation of the automatic failover process.

PostgreSQL
---------------
-  **admin**:
        -  **password**: admin password; user is created during initialization.
        -  **username**: admin username; user is created during initialization. It will have CREATEDB and CREATEROLE privileges.
-  **callbacks**: callback scripts to run on certain actions. Patroni will pass the action, role and cluster name. (See scripts/aws.py as an example of how to write them.)
        -  **on\_reload**: run this script when configuration reload is triggered.
        -  **on\_restart**: run this script when the cluster restarts.
        -  **on\_role\_change**: run this script when the cluster is being promoted or demoted.
        -  **on\_start**: run this script when the cluster starts.
        -  **on\_stop**: run this script when the cluster stops.
-  **connect\_address**: IP address + port through which Postgres is accessible from other nodes and applications.
-  **create\_replica\_methods**: an ordered list of the create methods for turning a Patroni node into a new replica. "basebackup" is the default method; other methods are assumed to refer to scripts, each of which is configured as its own config item.
-  **data\_dir**: file path to initialize and store Postgres data files.
-  **initdb**: List options to be passed on to initdb.
-  **data-checksums**: Must be enabled when pg_rewind is needed on 9.3.
-  **encoding**: default encoding for new databases.
-  **locale**: default locale for new databases.
-  **listen**: IP address + port that Postgres listens to; must be accessible from other nodes in the cluster, if you're using streaming replication. Multiple comma-separated addresses are permitted, as long as the port component is appended after to the last one with a colon, i.e. ``listen: 127.0.0.1,127.0.0.2:5432``. Patroni will use the first address from this list to establish local connections to the PostgreSQL node.
-  **maximum\_lag\_on\_failover**: the maximum bytes a follower may lag.
-  **name**: the name of the Postgres host. Must be unique for the cluster.
-  **pg\_hba**: list of lines that you should add to pg\_hba.conf.
        -  **- host all all 0.0.0.0/0 md5**.
        -  **- host replication replicator 127.0.0.1/32 md5**: A line like this is required for replication.
-  **recovery\_conf**: additional configuration settings written to recovery.conf when configuring follower.
        -  **parameters**: list of configuration settings for Postgres. Many of these are required for replication to work.
-  **replica\_method** for each create_replica_method other than basebackup, you would add a configuration section of the same name. At a minimum, this should include "command" with a full path to the actual script to be executed.  Other configuration parameters will be passed along to the script in the form "parameter=value".
-  **replication**:
        -  **username**: replication username; user will be created during initialization.
        -  **password**: replication password; user will be created during initialization.
-  **use\_slots**: whether or not to use replication_slots. Must be False for PostgreSQL 9.3. You should comment out max_replication_slots before it becomes ineligible for leader status.
-  **superuser**:
        -  **password**: password for the Postgres user, set during initialization.

REST API
-------- 
-  **connect\_address**: IP address and port through which restapi is accessible.
-  **listen**: IP address and port that Patroni will listen to, to provide health-check information for HAProxy.
- **Optional**:
        -  **auth**: 'username:password' to protect dangerous REST API endpoints.
        -  **certfile**: Specifies a file with the certificate in the PEM format. If the certfile is not specified or is left empty, the API server will work without SSL.
        -  **keyfile**: Specifies a file with the secret key in the PEM format.

ZooKeeper
----------
-  **hosts**: list of ZooKeeper cluster members in format: ['host1:port1', 'host2:port2', 'etc...'].
-  **reconnect\_timeout**: how long you should try to reconnect to ZooKeeper after a connection loss. After this timeout, assume that you no longer have a lock and restart in read-only mode.
-  **scope**: the relative path used on ZooKeeper for this deployment. Makes it possible to run multiple HA deployments from a single ZooKeeper cluster.
-  **session\_timeout**: the TTL to acquire the leader lock. Think of it as the length of time before initiation of the automatic failover process.

ZooKeeper Exhibitor
--------------------
If you are running a ZooKeeper cluster under the Exhibitor supervisory, this section might interest you:

-  **hosts**: initial list of Exhibitor (ZooKeeper) nodes in format: ['host1', 'host2', 'etc...' ]. This list updates automatically whenever the Exhibitor (ZooKeeper) cluster topology changes.
-  **poll\_interval**: how often the list of ZooKeeper and Exhibitor nodes should be updated from Exhibitor
-  **port**: Exhibitor port.