Connection closed abruptly

Last updated on Sep 05, 2022
Applies To FTP/SFTP Source
Error Message Text(s) Your Source server has closed the connection abruptly. Please try again or re-check your Source configuration.

Potential Causes

  • The error usually indicates that the Source server is dropping connections. This can happen because of too many parallel connection attempts being made to the server.

Suggested Action(s)

  • Update the MaxStartups config value in the /etc/sshd_config file on your SSH server to 50:10:100. This value indicates that there can be a maximum of 50 concurrent unauthenticated connections to the server, before additional connections start getting dropped. The probability of an additional connection being dropped is 10% when the number of connections is 50, and increases linearly with each additional connection attempt. All connection attempts are refused if the number of unauthenticated connections reaches 100.

  • Update the MaxSessions config value in the /etc/sshd_config file on your SSH server to 100.

  • Contact Hevo Support to increase the connection timeout value.

Note: Any update to the /etc/sshd_config file requires a restart of the SSH server to be applicable. On Debian-based systems, this can be done via the following command:

sudo systemctl restart ssh.service


Revision History

Refer to the following table for the list of key updates made to this page:

Date Release Description of Change
Sep-05-2022 NA Brought this page under its respective Source documentation folder.
Jun-21-2022 1.91 New document.

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