Symptoms

Publishing of a big site or if the site have a lot of small files fails with

2014-06-07T11:30:39+04:00       [ERR]   /JsonApi/       Cannot create directory 'webspace/httpdocs/data' on FTP target It is possible that there are not enough permissions for writing or there is not enough free space on the server.

Cause

FTP server timeouts aren't not enough

Resolution

Increase timeouts to recommended values

If you have a proFTP

/etc/proftpd.conf
TimeoutLogin            128
TimeoutIdle                     600
TimeoutNoTransfer       8192
TimeoutStalled          8192

For vsFTP, in vsftpd.conf file increase timeouts

idle_session_timeout=600
data_connection_timeout=600 

Internal content