[Dovecot] pop3-login: Fatal: io_loop_handle_add: epoll_ctl(1, 5):

[Mark Sapiro]

I have been running Dovecot 1.2.5 since Sept 14. Beginning at about
03:28 on Sept 21 for no apparent (to me) reason and continuing through
the present, I am seeing log messages like the following and am
experiencing delays logging in.

Sep 22 19:07:15 sbh16 dovecot: dovecot: Temporary failure in creating
login processes, slowing down for now
Sep 22 19:07:15 sbh16 dovecot: pop3-login: Fatal: io_loop_handle_add:
epoll_ctl(1, 5): Operation not permitted
Sep 22 19:07:48 sbh16 dovecot: pop3-login: Login: user=<mark>,
method=APOP, rip=68.183.193.239, lip=72.52.113.16, TLS
Sep 22 19:07:48 sbh16 dovecot: POP3(mark): Disconnected: Logged out
top=0/0, retr=0/0, del=0/218, size=2550090
Sep 22 19:08:15 sbh16 dovecot: dovecot: Created login processes
successfully, unstalling
Sep 22 19:08:15 sbh16 dovecot: dovecot: Temporary failure in creating
login processes, slowing down for now
Sep 22 19:08:15 sbh16 dovecot: dovecot: child 21735 (login) returned
error 89 (Fatal failure)
Sep 22 19:08:15 sbh16 dovecot: pop3-login: Fatal: io_loop_handle_add:
epoll_ctl(1, 5): Operation not permitted
Sep 22 19:08:21 sbh16 dovecot: pop3-login: Login: user=<mark>,
method=APOP, rip=68.183.193.239, lip=72.52.113.16, TLS
Sep 22 19:08:22 sbh16 dovecot: POP3(mark): Disconnected: Logged out
top=0/0, retr=1/57566, del=0/218, size=2550090
Sep 22 19:09:15 sbh16 dovecot: dovecot: Created login processes
successfully, unstalling

Is this a dovecot issue, some other issue or perhaps some kind of
denial of service attack?

Here's my dovecot -n

# 1.2.5: /usr/local/etc/dovecot.conf
# OS: Linux 2.6.18-8.1.14.el5 i686 CentOS release 5 (Final)
protocols: pop3 pop3s imap imaps
ssl_cert_file: /etc/postfix/sbh16-cert.pem
ssl_key_file: /etc/postfix/sbh16-key.pem
login_dir: /usr/local/var/run/dovecot/login
login_executable(default): /usr/local/libexec/dovecot/imap-login
login_executable(imap): /usr/local/libexec/dovecot/imap-login
login_executable(pop3): /usr/local/libexec/dovecot/pop3-login
mail_privileged_group: mail
mail_location: mbox:~/Mail:INBOX=/var/spool/mail/%u
mbox_write_locks: fcntl dotlock
mail_executable(default): /usr/local/libexec/dovecot/imap
mail_executable(imap): /usr/local/libexec/dovecot/imap
mail_executable(pop3): /usr/local/libexec/dovecot/pop3
mail_plugin_dir(default): /usr/local/lib/dovecot/imap
mail_plugin_dir(imap): /usr/local/lib/dovecot/imap
mail_plugin_dir(pop3): /usr/local/lib/dovecot/pop3
lda:
  postmaster_address: postmaster at example.com
auth default:
  mechanisms: plain apop login
  worker_max_count: 5
  passdb:
    driver: passwd-file
    args: /usr/local/etc/dovecot.passwd
  passdb:
    driver: pam
  userdb:
    driver: passwd
  socket:
    type: listen
    client:
      path: /var/spool/postfix/private/auth
      mode: 432
      user: postfix
      group: postfix
[root at sbh16 ~]#
 
-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan