27.09.2013 17:52, Timo Sirainen <tss@iki.fi>

On 27.9.2013, at 11.31, Oleksii Krykun <kryol@bigmir.net> wrote:

...

I have dovecot-2.2.5 installed as part of postfix+dovecot+mysql+amavisd. My server has two NICs (Internet and local). /etc/resolv.conf point to ISP DNS. Local names are not resolved.

If ISP link goes to down state I see (after about 1minute) a following error:

Sep 26 15:44:29 pop3-login: Error: master(pop3): Auth request timed out (received 0/12 bytes)

auth process is hanging.

...

and following informational message:

Sep 26 15:44:29 pop3-login: Info: Internal login failure (pid=12809 id=17815) (internal failure, 1 successful auths): user=<xxx@xxx.xxx> .....

If link is restored (even for a short time) all works fine again. After next down errors are repeated.

I suppose that this is dns issue. Am I wrong?

Could be.

...

And I have a following question. Is it possible to disable dns requests? I haven't external clients. Or I must fix a name resolution e.g. to use a caching dns server?

Dovecot doesn't do DNS requests itself, exactly because of problems like these. Your passdb or userdb might do that though. Show your doveconf -n?

My doveconf -n:

2.2.5: /usr/local/etc/dovecot/dovecot.conf

OS: FreeBSD 8.4-RELEASE i386 ufs

auth_mechanisms = plain login cram-md5 auth_verbose = yes auth_verbose_passwords = plain dict { expire = mysql:/usr/local/etc/dovecot/dovecot-dict-expire.conf.ext } first_valid_gid = 1991 first_valid_uid = 1991 info_log_path = /var/log/dovecot-info.log log_path = /var/log/dovecot.log login_greeting = Welcome to IMAP/POP3 server login_trusted_networks = 127.0.0.0/8, 10.1.1.0/24 mail_location = maildir:/usr/local/mail/%d/%u mail_plugins = quota expire mail_privileged_group = mail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date ihave vnd.dovecot.duplicate namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { args = /usr/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { expire = Trash expire2 = Trash/* expire3 = Spam expire_dict = proxy::expire quota = maildir:User quota quota_warning = storage=95%% quota-warning 95 %u sieve = ~/.dovecot.sieve sieve_before = /usr/local/etc/dovecot/sieve/before.sieve sieve_dir = ~/sieve sieve_extensions = +vnd.dovecot.duplicate sieve_global_dir = /usr/local/etc/dovecot/sieve } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { group = virtual mode = 0666 user = virtual } } service dict { unix_listener dict { mode = 0600 user = virtual } } service imap-login { process_min_avail = 5 service_count = 0 } service pop3-login { service_count = 0 } service quota-warning { executable = script /usr/local/etc/dovecot/quota-warning.sh unix_listener quota-warning { user = virtual } user = dovecot } ssl_cert = </etc/ssl/certs/dovecot.pem ssl_key = </etc/ssl/private/dovecot.pem userdb { args = /usr/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } protocol lda { mail_plugins = quota expire sieve } protocol imap { imap_client_workarounds = delay-newmail tb-extra-mailbox-sep tb-lsub-flags mail_plugins = quota expire imap_quota } protocol pop3 { pop3_client_workarounds = outlook-no-nuls oe-ns-eoh

27.09.2013 18:29, Robert Schetterer <rs@sys4.de>

Am 27.09.2013 17:21, schrieb Oleksii Krykun:

...

...

If ISP link goes to down state I see (after about 1minute) a following error:

...

...

Sep 26 15:44:29 pop3-login: Error: master(pop3): Auth request timed out (received 0/12 bytes)

auth process is hanging.

perhaps check if there is some other stuff done when link goes down, like ntpdate configured with some if-down script relation etc

No. But during usual work sometimes I can see (with tcpdump) some PTR requests after pop3/imap client connection.

Best Regards MfG Robert Schetterer

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