Unable to complete backup over SFTP

[castrelo02]

NC 24.0.4 Backup app 113

Backup fails after writing some metadata to external storage. Fails when the backup is configured to write over sftp

Any idea?

/home/user/cloud $ php occ backup:point:create
> maintenance mode: on
> initialization of the AppData
> initialization of the RestoringPoint: 20220905085730-full-cwsnFq9muHLAMoe based on NC24.0.4.1
> initialization of the storage
> preparation of the data to be stored in the restoring point
> preparation of internal data
> maintenance mode: off
An unhandled exception has been thrown:
TypeError: fwrite(): Argument #1 ($stream) must be of type resource, bool given in /home/user/cloud/lib/private/Files/Storage/Common.php:209
Stack trace:
#0 /home/user/cloud/lib/private/Files/Storage/Common.php(209): fwrite(false, '')
#1 /home/user/cloud/lib/private/Files/Storage/Wrapper/Wrapper.php(258): OC\Files\Storage\Common->file_put_contents('backup/20220905...', '')
#2 /home/user/cloud/lib/private/Files/Storage/Wrapper/PermissionsMask.php(112): OC\Files\Storage\Wrapper\Wrapper->file_put_contents('backup/20220905...', '')
#3 /home/user/cloud/lib/private/Files/Storage/Wrapper/Wrapper.php(258): OC\Files\Storage\Wrapper\PermissionsMask->file_put_contents('backup/20220905...', '')
#4 /home/user/cloud/lib/private/Files/Storage/Wrapper/Availability.php(274): OC\Files\Storage\Wrapper\Wrapper->file_put_contents('backup/20220905...', '')
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