CURL.SetOptionUpkeepIntervalMS
------------------------------

Connection upkeep interval.

| Component | Version | macOS | Windows | Linux | Server | iOS SDK |
|---|---|---|---|---|---|---|
| [CURL](component_CURL.md) | [8.5](newinversion85.md) | ✅ Yes | ✅ Yes | ✅ Yes | ✅ Yes | ✅ Yes |

MBS( "CURL.SetOptionUpkeepIntervalMS"; curl; Value ) 

**MBS**( **"CURL.SetOptionUpkeepIntervalMS";** /\* Connection upkeep interval. \*/  
**$curl**; /\* The CURL session handle. \*/   
**$Value**) /\* The new interval. \*/ 

### Parameters

| Parameter | Description | Example |
|---|---|---|
| curl | The CURL session handle. | $curl |
| Value | The new interval. |  |

### Result

Returns OK or error.

### Description

Connection upkeep interval.  
Some protocols have "connection upkeep" mechanisms. These mechanisms usually send some traffic on existing connections in order to keep them alive; this can prevent connections from being closed due to overzealous firewalls, for example.  
  
The user needs to explicitly call Upkeep in order to perform the upkeep work.  
  
Currently the only protocol with a connection upkeep mechanism is HTTP/2: when the connection upkeep interval is exceeded and Upkeep is called, an HTTP/2 PING frame is sent on the connection.  
See also [UPKEEP\_INTERVAL\_MS](https://curl.haxx.se/libcurl/c/CURLOPT_UPKEEP_INTERVAL_MS.html) option in CURL manual.

### Examples

Keep connection alive in 30 seconds interval:

 MBS ( "CURL.SetOptionUpkeepIntervalMS"; $curl ; 30000 )  
### See also

- [CURL.SetOptionTCPKeepInterval](CURLSetOptionTCPKeepInterval.md)
- [CURL.Upkeep](CURLUpkeep.md)

### Release notes

- **Version 15.1**
    - Implemented keep alive for MQTT feature in [CURL](https://www.mbsplugins.eu/component_CURL.shtml) functions. Use [CURL.SetOptionUpkeepIntervalMS](https://www.mbsplugins.eu/CURLSetOptionUpkeepIntervalMS.shtml) function to enable.
- **Version 8.5**
    - Added [CURL.SetOptionDOHURL](http://www.mbsplugins.eu/CURLSetOptionDOHURL.shtml), [CURL.SetOptionUpkeepIntervalMS](http://www.mbsplugins.eu/CURLSetOptionUpkeepIntervalMS.shtml), [CURL.SetOptionUploadBufferSize](http://www.mbsplugins.eu/CURLSetOptionUploadBufferSize.shtml) and [CURL.Upkeep](http://www.mbsplugins.eu/CURLUpkeep.shtml).

### Blog Entries

- [MBS FileMaker Plugin, version 15.1pr4](https://www.mbsplugins.de/archive/2025-02-17/MBS_FileMaker_Plugin_version_1/monkeybreadsoftware_blog_filemaker)
- [MBS FileMaker Plugin, version 8.5pr5](https://www.mbsplugins.de/archive/2018-11-02/MBS_FileMaker_Plugin_version_8/monkeybreadsoftware_blog_filemaker)

Created 31st October 2018 , last changed 12nd May 2026

  
[CURL.SetOptionUnrestrictedAuth](CURLSetOptionUnrestrictedAuth.md) - [CURL.SetOptionUpload](CURLSetOptionUpload.md)

[HTML Version](CURLSetOptionUpkeepIntervalMS.shtml)