Plesk 12.0.18 Update #70, Ubuntu 14.04.3 LTS.
Our postfix mail log file is filled with millions of lines like the following:
Oct 28 17:00:42 cloud8 plesk_saslauthd[17698]: activity on 1 channel(s)
Oct 28 17:00:42 cloud8 plesk_saslauthd[17698]: new client (fd=10) registered
Oct 28 17:00:42...