- Plesk for Linux
Scheduled backup to a remote FTP server failed:
PLESK_ERROR: pmm-ras failed (Error code = 1):
STDOUT: Curl error: Unable to resume an interrupted download: (28) Timeout was reached: Last FTP request: PASS *****: Last FTP response: 421 I can't accept more than 3 connections as the same user: Connection to the FTP server has lost
/var/log/plesk/PMM/backup-*/pmmcli.log and /var/log/plesk/PMM/pmmcli.log files contain the following error:
CONFIG_TEXT: [type 'exceptions.TypeError'] cannot concatenate 'str' and 'list' objects
TypeError: cannot concatenate 'str' and 'list' objects
[error][module]pmmcli[/module][operation]<type 'exceptions.TypeError'>[/operation][message]cannot concatenate 'str' and 'list' objects at File "/usr/local/psa/admin/sbin/pmmcli", line 6, in <module>
CONFIG_TEXT: INFO: Curl error: (28) Timeout was reached: Last FTP request: PASS *****: Last FTP response: 421 I can't accept more than 3 connections as the same user
Additionally, a backup from FTP server cannot be restored with the following error, even though the backups was created on a same Plesk server:
PLESK_ERROR: Error: The backup you are trying to restore was created in an unsupported version of Plesk and can not be recovered. Use the Plesk Migrator extension to transfer your data from legacy Plesk versions.
This is a Plesk bug #PPPM-8749 that will be fixed in future product updates: FTP server has limit on number of connections and Plesk backup cannot upload the file correctly.
As a workaround, do the following:
- Connect to the server via SSH
- Add the option
ftpForbidReuseConnection = 1
This way the number of used connections during backups creation will be decreased so that a remote FTP server can handle this type of connection.
As an alternative workaround, increase the limit of number of connections on the FTP server side.