Loading

Marketing Cloud Engagement | Causes and Resolutions for Intermittent SFTP Connection Errors to Enhanced FTP Sites

Дата публикации: Apr 22, 2026
Описание

If you encounter errors or connection resets (RST) during an SFTP connection to the Marketing Cloud Engagement Enhanced FTP site, the cause is typically a transient issue along the internet network path. Therefore, the most effective countermeasure is to incorporate a retry mechanism into your manual workflows or automated scripts. This article explains the background of these errors, troubleshooting steps, and the importance of implementing retry logic.

Решение
Even when MCE services are operating normally, file transfers using SFTP to the Marketing Cloud Engagement Enhanced FTP Site may fail due to intermittent connection errors, disconnections, or connection resets (RST). Connection resets occur when a device along the network path forcibly terminates the connection, and often appear as I/O exceptions (IOException) on the client side. These transient errors are typically caused by temporary internet-side problems, not by MCE services or client-side configurations, and are often impossible to prevent or isolate.
Note that the same concepts apply to SFTP transfer speed delays and intermittent connection errors from MCE File Transfer Activities to external SFTP sites or cloud storage.

 

The following sections explain the background of these errors and recommended actions.

 

Root Causes of Errors

SFTP connections are established between the client and the server over the internet. The internet is a "best-effort" network, meaning communication quality is not guaranteed. Temporary network congestion or packet loss on the route can cause unexpected disconnections or connection errors. For this reason, sporadic, intermittent errors can occur even when there are no issues with our services or the client's environment. Investigating and preventing these specific causes is difficult.
Additionally, Marketing Cloud Engagement operates in a "multi-tenant" environment where resources are shared among many customers. It is possible that high-load processes from other tenants may temporarily affect your SFTP performance. For these reasons, we strongly recommend implementing an effective retry strategy as described in the next section.

The Most Effective Solution: Implement Retry Logic

Based on the premise that intermittent errors are unavoidable, it is strongly recommended to implement robust retry logic in any automated file transfer scripts. This will significantly improve the stability of your system.
When implementing retries, a simple "wait and retry" method can be used, or a more advanced approach such as "exponential backoff" is also beneficial.
 
  • Exponential Backoff: A strategy where the wait time before the next retry increases exponentially after each failure (e.g., 1 second, 2 seconds, 4 seconds, 8 seconds...).

Troubleshooting Steps When Retries Fail

If errors persist and retry logic does not resolve the issue, use the following steps to systematically isolate the problem. Note that since all traffic passes through the internet, many devices along the path may be involved. We recommend investigating any other suspicious components as needed.
 
Step 1: Check the Salesforce Trust Site
Go to status.salesforce.com and check if any service disruptions or maintenance are reported for your instance (MID). If an issue with the Enhanced FTP Site is reported, please wait for updates on that event.

 

Step 2: Validate Client Configuration and Software
If the error occurs in an automated script, try connecting and transferring files manually using a standard SFTP client tool from the same machine with the same credentials. If the manual connection and transfer succeed, the problem is very likely within the script's logic or the libraries it uses.
 
Step 3: Diagnose the Network Path
If you cannot connect even with a standard SFTP client, a network path issue is suspected. Run traceroute from your Command Prompt or Terminal to the Enhanced FTP Site endpoint and review the results for significant, consecutive delays or timeouts at any specific hop on the route.
 
Note on Rare Cases: In rare cases, a specific internet connection may experience continuous, degraded performance. If you have access to a different internet connection, try transferring to the Enhanced FTP site from that environment. If the transfer succeeds, it indicates a problem with the original connection.

Information Required When Contacting Support

If you have completed all the troubleshooting steps above, the issue is not resolved, and you believe the cause is not the client or network path, please gather the following information and consider contacting Salesforce Support. Including the following in your case will help expedite the investigation:
  • Exact date and time (including time zone) when the error occurred
  • Approximate frequency of the error
  • The full, verbatim error message
  • Your source public IP address
  • The traceroute results
  • Confirmation that the issue is reproducible on other SFTP clients
Notes
  • Our investigation will focus primarily on the operational status of the Enhanced FTP Site service we provide.
  • Please note that while you may be asked to confirm logs on the Enhanced FTP Site during the investigation, we are unable to provide the raw log files themselves.
Номер статьи базы знаний

005226683

 
Загрузка
Salesforce Help | Article