From my secure log:
Sep 19 01:16:44 lin12 dovecot-auth: pam_unix(dovecot:auth): check pass; user unknown Sep 19 01:16:44 lin12 dovecot-auth: pam_unix(dovecot:auth): authentication failure; logname= uid=0 euid=0 tty=dovecot ruser= rhost=::ffff:64.31.19.48 Sep 19 01:16:44 lin12 dovecot-auth: pam_succeed_if(dovecot:auth): error retrieving information about user aaron Sep 19 01:16:45 lin12 dovecot-auth: pam_unix(dovecot:auth): check pass; user unknown Sep 19 01:16:45 lin12 dovecot-auth: pam_unix(dovecot:auth): authentication failure; logname= uid=0 euid=0 tty=dovecot ruser= rhost=::ffff:64.31.19.48 Sep 19 01:16:45 lin12 dovecot-auth: pam_succeed_if(dovecot:auth): error retrieving information about user abby
etc. Literally, 30,000 user names attempted.
rick baartman
TRIUMF 4004 Wesbrook Mall Vancouver, BC V6T2A3