# Set a PostgreSQL Maintenance Window

If you do not choose a maintenance window during the creation of your database, a system-defined maintenance window will be assigned to your database. You can update the window at any time, as shown in the [<mark style="color:blue;">example</mark>](#request). For more information, see [<mark style="color:blue;">Maintenance Window</mark>](/cloud/databases/postgresql/overview/maintenance-window.md).

## Endpoint

Use the following endpoint to set a PostgreSQL maintenance window:`https://api.ionos.com/databases/postgresql/clusters/{clusterId}`

{% hint style="info" %}
**Note:** The sample UUID is `498ae72f-411f-11eb-9d07-046c59cc737e`.
{% endhint %}

## Request

```bash
curl --include \
    --request PATCH \
    --user "clientname@ionos.com:Mb2.r5oHf-0t" \
    --header "Content-Type: application/json" \
    --data-binary '{
      "metadata": {},
      "properties": {
        "maintenanceWindow": {
          "dayOfTheWeek": "Sunday",
          "time": "03:30:00"
        }
      }
    }' \
```

## Response

```json
{
  "type": "cluster",
  "id": "498ae72f-411f-11eb-9d07-046c59cc737e",
  "metadata": {
    "state": "AVAILABLE",
    "createdDate": "2020-12-10T12:37:50.000Z",
    "createdBy": "clientname@ionos.com",
    "createdByUserId": "012342f-411f-1eeb-9d07-046c59cc737e",
    "lastModifiedDate": "2020-12-18T21:37:50.000Z",
    "lastModifiedBy": "clientname@ionos.com",
    "lastModifiedByUserId": "012342f-411f-1eeb-9d07-046c59cc737e"
  },
"properties": {
        "displayName": "an even better name",
        "location": "de/txl",
        "dnsName": "pg-pgov71sjg1c875ji.postgresql.de-txl.ionos.com",
        "connections": [
            {
                "datacenterId": "db7e8811-cfae-4b40-82ee-2f4cff81e105",
                "lanId": "2",
                "cidr": "10.7.222.3/23"
            }
        ],
        "cores": 4,
        "postgresVersion": "15",
        "ram": 4096,
        "instances": 1,
        "storageSize": 102400,
        "storageType": "HDD",
        "maintenanceWindow": {
            "dayOfTheWeek": "Sunday",
            "time": "03:30:00"
        },
        "synchronizationMode": "ASYNCHRONOUS",
        "connectionPooler": {
            "enabled": false,
            "poolMode": "transaction"
        }
    }
}
```

## Response

```json
{
  "type": "cluster",
  "id": "498ae72f-411f-11eb-9d07-046c59cc737e",
  "metadata": {
    "state": "AVAILABLE",
    "createdDate": "2020-12-10T12:37:50.000Z",
    "createdBy": "clientname@ionos.com",
    "createdByUserId": "012342f-411f-1eeb-9d07-046c59cc737e",
    "lastModifiedDate": "2020-12-18T21:37:50.000Z",
    "lastModifiedBy": "clientname@ionos.com",
    "lastModifiedByUserId": "012342f-411f-1eeb-9d07-046c59cc737e"
  },
    "properties": {
        "displayName": "an even better name",
        "location": "de/txl",
        "dnsName": "pg-pgov71sjg1c875ji.postgresql.de-txl.ionos.com",
        "connections": [
            {
                "datacenterId": "db7e8811-cfae-4b40-82ee-2f4cff81e105",
                "lanId": "2",
                "cidr": "10.7.222.3/23"
            }
        ],
        "cores": 4,
        "postgresVersion": "15",
        "ram": 4096,
        "instances": 1,
        "storageSize": 102400,
        "storageType": "HDD",
        "maintenanceWindow": {
            "dayOfTheWeek": "Wednesday",
            "time": "12:08:00"
        },
        "synchronizationMode": "ASYNCHRONOUS",
        "connectionPooler": {
            "enabled": false,
            "poolMode": "transaction"
        }
    }
  }
```

{% hint style="danger" %}
**Caution:** When your cluster contains only one replica, you may experience a short downtime during this maintenance window while your database instance is being updated. In a replicated cluster, we only update standbys; however, we may perform a switchover to change the leader node.
{% endhint %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.ionos.com/cloud/databases/postgresql/api/v1-api/modify-cluster-attributes/set-a-postgresql-maintenance-window.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.