I'm trying to upload files to a VPS over SFTP. Unfortunately, I'm having a strange problem.
While uploading a file over SFTP as root, the transfer appears to randomly stops somewhere in the first few KB. Filezilla reports that the connection timed out, and Cyberduck reports that the socket was closed. Over SSH the partially uploaded file appears to be truncated to point where the upload stopped.
grep -ir sftp /var/log/* shows no errors.
I'm running centOS with fail2ban and Shorewall, if those are relevant.
I'm fairly new to this, so it might be something really basic.