Patroni REST API

Reference for Patroni REST API endpoints and operational behaviors.

Source: https://patroni.readthedocs.io/en/latest/rest_api.html

Patroni uses its REST API during leader races. patronictl uses it for failovers, switchovers, reinitialization, restarts, and reloads. HAProxy and other load balancers use it for HTTP health checks. Monitoring systems can also use it. This page lists the available endpoints.

Health check endpoints

Health check GET requests return an HTTP status code and a JSON document with node status. Use HEAD or OPTIONS instead of GET if you do not need JSON.

The following requests to Patroni REST API will return HTTP status code 200 only when the Patroni node is running as the primary with leader lock:
- GET /
- GET /primary
- GET /read-write
GET /standby-leader: returns HTTP status code 200 only when the Patroni node is running as the leader in a standby cluster.
GET /leader: returns HTTP 200 if the node holds the leader lock. Unlike the preceding endpoints, it does not distinguish PostgreSQL roles primary and standby_leader.
GET /replica: returns HTTP 200 only if the node is running, its role is replica, and noloadbalance is unset.
GET /replica?replication_state=<required state>: adds a replication state check to replica. Use replication_state=streaming to exclude replicas still catching up through archive recovery.
GET /replica?lag=<max-lag>: adds a lag check to replica. HTTP 200 requires lag below the limit. For performance, Patroni uses DCS cluster.last_leader_operation as the leader WAL position to calculate lag. Specify max-lag as an integer byte count or a readable value, such as 16kB, 64MB, or 1GB.
- GET /replica?lag=1048576
- GET /replica?lag=1024kB
- GET /replica?lag=10MB
- GET /replica?lag=1GB
GET /replica?tag_key1=value1&tag_key2=value2: also checks custom key1 and key2 tags in the YAML tags section. An undefined tag or a value different from the query value returns HTTP 503.
The following requests check leader or standby leader status. They ignore custom tags:
- GET /?tag_key1=value1&tag_key2=value2
- GET /leader?tag_key1=value1&tag_key2=value2
- GET /primary?tag_key1=value1&tag_key2=value2
- GET /read-write?tag_key1=value1&tag_key2=value2
- GET /standby_leader?tag_key1=value1&tag_key2=value2
- GET /standby-leader?tag_key1=value1&tag_key2=value2
GET /read-only: like the above endpoint, but also includes the primary.
GET /synchronous or GET /sync: returns HTTP status code 200 only when the Patroni node is running as a synchronous standby.
GET /read-only-sync: like the above endpoint, but also includes the primary.
GET /quorum: returns HTTP status code 200 only when this Patroni node is listed as a quorum node in synchronous_standby_names on the primary.
GET /read-only-quorum: like the above endpoint, but also includes the primary.
GET /asynchronous or GET /async: returns HTTP status code 200 only when the Patroni node is running as an asynchronous standby.
GET /asynchronous?lag=<max-lag> or GET /async?lag=<max-lag>: adds a lag check to asynchronous or async. HTTP 200 requires lag below the limit. For performance, Patroni uses DCS cluster.last_leader_operation as the leader WAL position to calculate lag. Specify max-lag as an integer byte count or a readable value, such as 16kB, 64MB, or 1GB.
- GET /async?lag=1048576
- GET /async?lag=1024kB
- GET /async?lag=10MB
- GET /async?lag=1GB
GET /health: returns HTTP status code 200 only when PostgreSQL is up and running.
GET /liveness: returns HTTP 200 if the heartbeat loop operates correctly. Returns 503 if the last run was more than ttl seconds ago on the primary or 2*ttl on a replica. Use this for livenessProbe.
GET /readiness?lag=<max-lag>&mode=apply|write: returns HTTP 200 for a leader or a running, replicating node within the lag limit. The lag parameter limits standby lag and defaults to maximum_lag_on_failover. Use bytes or readable values, such as 16kB, 64MB, or 1GB. Mode specifies whether WAL must be replayed (apply) or only received (write). The default is apply.
As a Kubernetes readinessProbe, this prevents new pods from becoming ready before they catch up to the leader. With a PodDisruptionBudget, it prevents premature leader termination during rolling restarts. It also excludes replicas that cannot keep up from read-only traffic. Use this endpoint for readinessProbe where Kubernetes endpoints cannot support leader elections, such as OpenShift.

The liveness endpoint is lightweight and runs no SQL. Configure probes to start failing around leader key expiration. With the default ttl of 30s, use this example:

readinessProbe:
  httpGet:
    scheme: HTTP
    path: /readiness
    port: 8008
  initialDelaySeconds: 3
  periodSeconds: 10
  timeoutSeconds: 5
  successThreshold: 1
  failureThreshold: 3
livenessProbe:
  httpGet:
    scheme: HTTP
    path: /liveness
    port: 8008
  initialDelaySeconds: 3
  periodSeconds: 10
  timeoutSeconds: 5
  successThreshold: 1
  failureThreshold: 3

Monitoring endpoint

Patroni uses GET /patroni during leader races. Monitoring systems can also use it. Its JSON structure matches the health check endpoints.

Example: A healthy cluster

$ curl -s http://localhost:8008/patroni | jq .
{
  "state": "running",
  "postmaster_start_time": "2024-08-28 19:39:26.352526+00:00",
  "role": "primary",
  "server_version": 160004,
  "xlog": {
    "location": 67395656
  },
  "timeline": 1,
  "replication": [
    {
      "usename": "replicator",
      "application_name": "patroni2",
      "client_addr": "10.89.0.6",
      "state": "streaming",
      "sync_state": "async",
      "sync_priority": 0
    },
    {
      "usename": "replicator",
      "application_name": "patroni3",
      "client_addr": "10.89.0.2",
      "state": "streaming",
      "sync_state": "async",
      "sync_priority": 0
    }
  ],
  "dcs_last_seen": 1692356718,
  "tags": {
    "clonefrom": true
  },
  "database_system_identifier": "7268616322854375442",
  "patroni": {
    "version": "4.0.0",
    "scope": "demo",
    "name": "patroni1"
  }
}

Example: An unlocked cluster

$ curl -s http://localhost:8008/patroni  | jq .
{
  "state": "running",
  "postmaster_start_time": "2024-08-28 19:39:26.352526+00:00",
  "role": "replica",
  "server_version": 160004,
  "xlog": {
    "received_location": 67419744,
    "replayed_location": 67419744,
    "replayed_timestamp": null,
    "paused": false
  },
  "timeline": 1,
  "replication": [
    {
      "usename": "replicator",
      "application_name": "patroni2",
      "client_addr": "10.89.0.6",
      "state": "streaming",
      "sync_state": "async",
      "sync_priority": 0
    },
    {
      "usename": "replicator",
      "application_name": "patroni3",
      "client_addr": "10.89.0.2",
      "state": "streaming",
      "sync_state": "async",
      "sync_priority": 0
    }
  ],
  "cluster_unlocked": true,
  "dcs_last_seen": 1692356928,
  "tags": {
    "clonefrom": true
  },
  "database_system_identifier": "7268616322854375442",
  "patroni": {
    "version": "4.0.0",
    "scope": "demo",
    "name": "patroni1"
  }
}

Example: An unlocked cluster with DCS failsafe mode enabled

$ curl -s http://localhost:8008/patroni  | jq .
{
  "state": "running",
  "postmaster_start_time": "2024-08-28 19:39:26.352526+00:00",
  "role": "replica",
  "server_version": 160004,
  "xlog": {
    "location": 67420024
  },
  "timeline": 1,
  "replication": [
    {
      "usename": "replicator",
      "application_name": "patroni2",
      "client_addr": "10.89.0.6",
      "state": "streaming",
      "sync_state": "async",
      "sync_priority": 0
    },
    {
      "usename": "replicator",
      "application_name": "patroni3",
      "client_addr": "10.89.0.2",
      "state": "streaming",
      "sync_state": "async",
      "sync_priority": 0
    }
  ],
  "cluster_unlocked": true,
  "failsafe_mode_is_active": true,
  "dcs_last_seen": 1692356928,
  "tags": {
    "clonefrom": true
  },
  "database_system_identifier": "7268616322854375442",
  "patroni": {
    "version": "4.0.0",
    "scope": "demo",
    "name": "patroni1"
  }
}

Example: A cluster with the pause mode enabled

$ curl -s http://localhost:8008/patroni  | jq .
{
  "state": "running",
  "postmaster_start_time": "2024-08-28 19:39:26.352526+00:00",
  "role": "replica",
  "server_version": 160004,
  "xlog": {
    "location": 67420024
  },
  "timeline": 1,
  "replication": [
    {
      "usename": "replicator",
      "application_name": "patroni2",
      "client_addr": "10.89.0.6",
      "state": "streaming",
      "sync_state": "async",
      "sync_priority": 0
    },
    {
      "usename": "replicator",
      "application_name": "patroni3",
      "client_addr": "10.89.0.2",
      "state": "streaming",
      "sync_state": "async",
      "sync_priority": 0
    }
  ],
  "pause": true,
  "dcs_last_seen": 1724874295,
  "tags": {
    "clonefrom": true
  },
  "database_system_identifier": "7268616322854375442",
  "patroni": {
    "version": "4.0.0",
    "scope": "demo",
    "name": "patroni1"
  }
}

Retrieve the Patroni metrics in Prometheus format through the GET /metrics endpoint.

$ curl http://localhost:8008/metrics

# HELP patroni_version Patroni semver without periods. \
# TYPE patroni_version gauge
patroni_version{scope="batman",name="patroni1"} 040000
# HELP patroni_postgres_running Value is 1 if Postgres is running, 0 otherwise.
# TYPE patroni_postgres_running gauge
patroni_postgres_running{scope="batman",name="patroni1"} 1
# HELP patroni_postmaster_start_time Epoch seconds since Postgres started.
# TYPE patroni_postmaster_start_time gauge
patroni_postmaster_start_time{scope="batman",name="patroni1"} 1724873966.352526
# HELP patroni_primary Value is 1 if this node is the leader, 0 otherwise.
# TYPE patroni_primary gauge
patroni_primary{scope="batman",name="patroni1"} 1
# HELP patroni_xlog_location Current location of the Postgres transaction log, 0 if this node is not the leader.
# TYPE patroni_xlog_location counter
patroni_xlog_location{scope="batman",name="patroni1"} 22320573386952
# HELP patroni_standby_leader Value is 1 if this node is the standby_leader, 0 otherwise.
# TYPE patroni_standby_leader gauge
patroni_standby_leader{scope="batman",name="patroni1"} 0
# HELP patroni_replica Value is 1 if this node is a replica, 0 otherwise.
# TYPE patroni_replica gauge
patroni_replica{scope="batman",name="patroni1"} 0
# HELP patroni_sync_standby Value is 1 if this node is a sync standby replica, 0 otherwise.
# TYPE patroni_sync_standby gauge
patroni_sync_standby{scope="batman",name="patroni1"} 0
# HELP patroni_quorum_standby Value is 1 if this node is a quorum standby replica, 0 otherwise.
# TYPE patroni_quorum_standby gauge
patroni_quorum_standby{scope="batman",name="patroni1"} 0
# HELP patroni_xlog_received_location Current location of the received Postgres transaction log, 0 if this node is not a replica.
# TYPE patroni_xlog_received_location counter
patroni_xlog_received_location{scope="batman",name="patroni1"} 0
# HELP patroni_xlog_replayed_location Current location of the replayed Postgres transaction log, 0 if this node is not a replica.
# TYPE patroni_xlog_replayed_location counter
patroni_xlog_replayed_location{scope="batman",name="patroni1"} 0
# HELP patroni_xlog_replayed_timestamp Current timestamp of the replayed Postgres transaction log, 0 if null.
# TYPE patroni_xlog_replayed_timestamp gauge
patroni_xlog_replayed_timestamp{scope="batman",name="patroni1"} 0
# HELP patroni_xlog_paused Value is 1 if the Postgres xlog is paused, 0 otherwise.
# TYPE patroni_xlog_paused gauge
patroni_xlog_paused{scope="batman",name="patroni1"} 0
# HELP patroni_postgres_streaming Value is 1 if Postgres is streaming, 0 otherwise.
# TYPE patroni_postgres_streaming gauge
patroni_postgres_streaming{scope="batman",name="patroni1"} 1
# HELP patroni_postgres_in_archive_recovery Value is 1 if Postgres is replicating from archive, 0 otherwise.
# TYPE patroni_postgres_in_archive_recovery gauge
patroni_postgres_in_archive_recovery{scope="batman",name="patroni1"} 0
# HELP patroni_postgres_server_version Version of Postgres (if running), 0 otherwise.
# TYPE patroni_postgres_server_version gauge
patroni_postgres_server_version{scope="batman",name="patroni1"} 160004
# HELP patroni_cluster_unlocked Value is 1 if the cluster is unlocked, 0 if locked.
# TYPE patroni_cluster_unlocked gauge
patroni_cluster_unlocked{scope="batman",name="patroni1"} 0
# HELP patroni_failsafe_mode_is_active Value is 1 if failsafe mode is active, 0 otherwise.
# TYPE patroni_failsafe_mode_is_active gauge
patroni_failsafe_mode_is_active{scope="batman",name="patroni1"} 0
# HELP patroni_failsafe_mode_enabled Value is 1 if failsafe_mode is enabled, 0 otherwise.
# TYPE patroni_failsafe_mode_enabled gauge
patroni_failsafe_mode_enabled{scope="batman",name="patroni1"} 0
# HELP patroni_failsafe_member Value is 1 if this node is a member of failsafe, 0 otherwise.
# TYPE patroni_failsafe_member gauge
patroni_failsafe_member{scope="batman",name="patroni1"} 0
# HELP patroni_postgres_timeline Postgres timeline of this node (if running), 0 otherwise.
# TYPE patroni_postgres_timeline gauge
patroni_postgres_timeline{scope="batman",name="patroni1"} 24
# HELP patroni_dcs_last_seen Epoch timestamp when DCS was last contacted successfully by Patroni.
# TYPE patroni_dcs_last_seen gauge
patroni_dcs_last_seen{scope="batman",name="patroni1"} 1724874235
# HELP patroni_pending_restart Value is 1 if the node needs a restart, 0 otherwise.
# TYPE patroni_pending_restart gauge
patroni_pending_restart{scope="batman",name="patroni1"} 1
# HELP patroni_is_paused Value is 1 if auto failover is disabled, 0 otherwise.
# TYPE patroni_is_paused gauge
patroni_is_paused{scope="batman",name="patroni1"} 1
# HELP patroni_postgres_state Numeric representation of Postgres state.
# Values: 0=initdb, 1=initdb_failed, 2=custom_bootstrap, 3=custom_bootstrap_failed, 4=creating_replica, 5=running, 6=starting, 7=bootstrap_starting, 8=start_failed, 9=restarting, 10=restart_failed, 11=stopping, 12=stopped, 13=stop_failed, 14=crashed
# TYPE patroni_postgres_state gauge
patroni_postgres_state{scope="batman",name="patroni1"} 5
# HELP patroni_failover_priority Failover priority of this node.
# TYPE patroni_failover_priority gauge
patroni_failover_priority{scope="batman",name="patroni1"} 1

PostgreSQL State Values

The patroni_postgres_state metric represents the current PostgreSQL state numerically. Monitoring and alerting systems can use it to track state changes. The PostgresqlState.get_metrics_description() static method generates these values.

Value	State Name	Description
0	initdb	Initializing new cluster
1	initdb_failed	Initialization of new cluster failed
2	custom_bootstrap	Running custom bootstrap script
3	custom_bootstrap_failed	Custom bootstrap script failed
4	creating_replica	Creating replica from primary
5	running	PostgreSQL is running normally
6	starting	PostgreSQL is starting up
7	bootstrap_starting	Starting after custom bootstrap
8	start_failed	PostgreSQL start failed
9	restarting	PostgreSQL is restarting
10	restart_failed	PostgreSQL restart failed
11	stopping	PostgreSQL is stopping
12	stopped	PostgreSQL is stopped
13	stop_failed	PostgreSQL stop failed
14	crashed	PostgreSQL has crashed

PostgreSQL State Values

Note

Existing numeric values never change, to preserve monitoring compatibility. Future states receive new values.

Cluster status endpoints

The GET /cluster endpoint generates a JSON document describing the current cluster topology and state:

$ curl -s http://localhost:8008/cluster | jq .
{
  "members": [
    {
      "name": "patroni1",
      "role": "leader",
      "state": "running",
      "api_url": "http://10.89.0.4:8008/patroni",
      "host": "10.89.0.4",
      "port": 5432,
      "timeline": 5,
      "tags": {
        "clonefrom": true
      }
    },
    {
      "name": "patroni2",
      "role": "replica",
      "state": "streaming",
      "api_url": "http://10.89.0.6:8008/patroni",
      "host": "10.89.0.6",
      "port": 5433,
      "timeline": 5,
      "tags": {
        "clonefrom": true
      },
      "receive_lag": 0,
      "receive_lsn": "0/4000060",
      "replay_lag": 0,
      "replay_lsn": "0/4000060",
      "lag": 0,
      "lsn": "0/4000060"
    }
  ],
  "scope": "demo",
  "scheduled_switchover": {
    "at": "2023-09-24T10:36:00+02:00",
    "from": "patroni1",
    "to": "patroni3"
  }
}

GET /history returns cluster switchover and failover history. Its format matches history files in pg_wal, with one addition: the timestamp when each timeline was created.

$ curl -s http://localhost:8008/history | jq .
[
  [
    1,
    25623960,
    "no recovery target specified",
    "2019-09-23T16:57:57+02:00"
  ],
  [
    2,
    25624344,
    "no recovery target specified",
    "2019-09-24T09:22:33+02:00"
  ],
  [
    3,
    25624752,
    "no recovery target specified",
    "2019-09-24T09:26:15+02:00"
  ],
  [
    4,
    50331856,
    "no recovery target specified",
    "2019-09-24T09:35:52+02:00"
  ]
]

Config endpoint

GET /config: Get the current version of the dynamic configuration:

$ curl -s http://localhost:8008/config | jq .
{
  "ttl": 30,
  "loop_wait": 10,
  "retry_timeout": 10,
  "maximum_lag_on_failover": 1048576,
  "postgresql": {
    "use_slots": true,
    "use_pg_rewind": true,
    "parameters": {
      "hot_standby": "on",
      "wal_level": "hot_standby",
      "max_wal_senders": 5,
      "max_replication_slots": 5,
      "max_connections": "100"
    }
  }
}

PATCH /config: Change the existing configuration.

$ curl -s -XPATCH -d \
    '{"loop_wait":5,"ttl":20,"postgresql":{"parameters":{"max_connections":"101"}}}' \
    http://localhost:8008/config | jq .
{
  "ttl": 20,
  "loop_wait": 5,
  "maximum_lag_on_failover": 1048576,
  "retry_timeout": 10,
  "postgresql": {
    "use_slots": true,
    "use_pg_rewind": true,
    "parameters": {
      "hot_standby": "on",
      "wal_level": "hot_standby",
      "max_wal_senders": 5,
      "max_replication_slots": 5,
      "max_connections": "101"
    }
  }
}

The above REST API call patches the existing configuration and returns the new configuration.

Check that the node applied the configuration. With loop_wait=5, it should log every 5 seconds. Changing “max_connections” requires restart, so the output should show “pending_restart”:

$ curl -s http://localhost:8008/patroni | jq .
{
  "database_system_identifier": "6287881213849985952",
  "postmaster_start_time": "2024-08-28 19:39:26.352526+00:00",
  "xlog": {
    "location": 2197818976
  },
  "timeline": 1,
  "dcs_last_seen": 1724874545,
  "database_system_identifier": "7408277255830290455",
  "pending_restart": true,
  "pending_restart_reason": {
    "max_connections": {
      "old_value": "100",
      "new_value": "101"
    }
  },
  "patroni": {
    "version": "4.0.0",
    "scope": "batman",
    "name": "patroni1"
  },
  "state": "running",
  "role": "primary",
  "server_version": 160004
}

Removing parameters:

To remove or reset a setting, patch it with null:

$ curl -s -XPATCH -d \
    '{"postgresql":{"parameters":{"max_connections":null}}}' \
    http://localhost:8008/config | jq .
{
  "ttl": 20,
  "loop_wait": 5,
  "retry_timeout": 10,
  "maximum_lag_on_failover": 1048576,
  "postgresql": {
    "use_slots": true,
    "use_pg_rewind": true,
    "parameters": {
      "hot_standby": "on",
      "unix_socket_directories": ".",
      "wal_level": "hot_standby",
      "max_wal_senders": 5,
      "max_replication_slots": 5
    }
  }
}

The above call removes postgresql.parameters.max_connections from the dynamic configuration.

PUT /config: unconditionally replace the complete dynamic configuration:

$ curl -s -XPUT -d \
    '{"maximum_lag_on_failover":1048576,"retry_timeout":10,"postgresql":{"use_slots":true,"use_pg_rewind":true,"parameters":{"hot_standby":"on","wal_level":"hot_standby","unix_socket_directories":".","max_wal_senders":5}},"loop_wait":3,"ttl":20}' \
    http://localhost:8008/config | jq .
{
  "ttl": 20,
  "maximum_lag_on_failover": 1048576,
  "retry_timeout": 10,
  "postgresql": {
    "use_slots": true,
    "parameters": {
      "hot_standby": "on",
      "unix_socket_directories": ".",
      "wal_level": "hot_standby",
      "max_wal_senders": 5
    },
    "use_pg_rewind": true
  },
  "loop_wait": 3
}

Switchover and failover endpoints

Switchover

The /switchover endpoint requires a healthy cluster with a leader. It can also schedule a future switchover.

A candidate is optional for /switchover but required for /failover. Without a candidate, all eligible nodes enter the leader race after the leader steps down.

The POST JSON body must include leader. Optional fields are candidate and scheduled_at. Use scheduled_at to schedule a future switchover.

HTTP 200 means switchover or failover completed successfully. HTTP 202 means Patroni scheduled the switchover. Errors return 400, 412, or 503, with details in the response body.

DELETE /switchover can be used to delete the currently scheduled switchover.

Example: perform a switchover to any healthy standby

$ curl -s http://localhost:8008/switchover -XPOST -d '{"leader":"postgresql1"}'
Successfully switched over to "postgresql2"

Example: perform a switchover to a specific node

$ curl -s http://localhost:8008/switchover -XPOST -d \
    '{"leader":"postgresql1","candidate":"postgresql2"}'
Successfully switched over to "postgresql2"

Example: schedule a switchover from the leader to any other healthy standby in the cluster at a specific time.

$ curl -s http://localhost:8008/switchover -XPOST -d \
    '{"leader":"postgresql0","scheduled_at":"2019-09-24T12:00+00"}'
Switchover scheduled

Failover

Use /failover for manual failover when no sufficiently healthy node is available. For example, promote an asynchronous standby when all synchronous standbys are unsuitable. A missing leader is not required: failover also works on a healthy cluster.

In the JSON body of the POST request you must specify the candidate field. If the leader field is specified, a switchover is triggered instead.

Example:

$ curl -s http://localhost:8008/failover -XPOST -d '{"candidate":"postgresql1"}'
Successfully failed over to "postgresql1"

Warning

Be very careful when using this endpoint, as this can cause data loss in certain situations. In most cases, the switchover endpoint satisfies the administrator’s needs.

POST /switchover and POST /failover endpoints are used by patronictl_switchover and patronictl_failover, respectively.

DELETE /switchover is used by patronictl flush cluster-name switchover.

	Failover	Switchover
Requires leader specified	no	yes
Requires candidate specified	yes	no
Can be run in pause	yes	yes (only to a specific candidate)
Can be scheduled	no	yes (if not in pause)

Failover/Switchover comparison

Healthy standby

A member must pass these checks to enter a switchover leader race or become the selected failover/switchover leader:

be reachable via Patroni API;
not have nofailover tag set to true;
have watchdog fully functional (if required by the configuration);
in case of a switchover in a healthy cluster or an automatic failover, not exceed maximum replication lag (maximum_lag_on_failover configuration parameter);
For a healthy-cluster switchover or automatic failover, check the check_timeline configuration parameter. If it is true, the member timeline must not be smaller than the cluster timeline;
in synchronous mode:
- In case of a switchover (both with and without a candidate): be listed in the /sync key members;
- For a failover in both healthy and unhealthy clusters, this check is omitted.

Warning

Without a leader, manual failover can promote a candidate that fails these checks. It can be absent from /sync in synchronous mode, exceed the lag limit, or have an older timeline than the last cluster timeline.

Restart endpoint

POST /restart: restart Postgres on the specified node. The POST JSON body can contain these optional conditions:
- restart_pending: if true, restart only when configuration changes require it.
- role: restart only if the current node role matches the request.
- postgres_version: restart only if the current Postgres version is lower than the requested version.
- timeout: maximum wait for PostgreSQL to accept connections. Overrides primary_start_timeout.
- schedule: future restart timestamp with time zone.
DELETE /restart: delete the scheduled restart.

POST /restart and DELETE /restart endpoints are used by patronictl_restart and patronictl flush cluster-name restart respectively.

Reload endpoint

POST /reload makes Patroni reread and apply its configuration file. This is equivalent to SIGHUP. Changes to parameters such as shared_buffers still require an explicit Postgres restart. Use POST /restart or patronictl_restart.

The reload endpoint is used by patronictl_reload.

Reinitialize endpoint

POST /reinitialize: recreate the data directory on the specified replica. This operation is not allowed on a primary. It removes the data directory and runs pg_basebackup or another replica creation method.

This call may fail while Patroni repeatedly tries to restart a failed Postgres instance. Set {"force":true} in the request body to override this condition.

Set {“from-leader”:true} in the request body to take the basebackup directly from the leader. Use this for reinitialization when all replicas have failed.

The reinitialize endpoint is used by patronictl_reinit.