Hello, I think I have a problem with my simple mail server. I noticed several bounce mails in the queue, which postfix in unable to deliver.
> C0B0160EC 12730 Thu Nov 8 12:35:47 MAILER-DAEMON > (lost connection with eforward5.registrar-servers.com[38.101.213.202] while > receiving the initial server greeting) > > instant.checkm...@designakeackson.info All of them destined to what look to be fake addresses. The original mails that originate the bounce are indeed spam. On this server I use spamassassin as content filter, which re-injects the mail into postfix after scanning it via local delivery. Spam is then discarded via a sieve rule (not bounced). It looks like postfix detects a mail forwarding loop when the mail is re-injected by spamassassin via local delivery. Why isn't the loop detected when the mail is received by the smtpd? I do not like to generate unnecessary bounce mails. Is this a real problem? How can I fix it? Here is what I think is a relevant log excerpt: > # egrep 2ABF060A6\|BCDF560EF\|C0B0160EC\|FD01D4DD-1DEF-1BC3-9A2A-5EDE8F9DD6C5 > /var/log/mail.log > Nov 8 12:35:46 zed postfix/smtpd[2515]: 2ABF060A6: > client=designakeackson.info[176.126.174.9] > Nov 8 12:35:46 zed postfix/cleanup[2517]: 2ABF060A6: > message-id=<fd01d4dd-1def-1bc3-9a2a-5ede8f9dd...@designakeackson.info> > Nov 8 12:35:46 zed postfix/qmgr[3850]: 2ABF060A6: > from=<instant.checkm...@designakeackson.info>, size=9793, nrcpt=1 (queue > active) > Nov 8 12:35:46 zed spamd[2282]: spamd: processing message > <fd01d4dd-1def-1bc3-9a2a-5ede8f9dd...@designakeackson.info> for daniele:1000 > Nov 8 12:35:47 zed spamd[2282]: spamd: result: Y 5 - > BAYES_50,HTML_MESSAGE,RP_MATCHES_RCVD,SPF_SOFTFAIL,T_FILL_THIS_FORM_SHORT,URIBL_DBL_SPAM,URIBL_JP_SURBL,URIBL_WS_SURBL > > scantime=1.4,size=9786,user=daniele,uid=1000,required_score=5.0,rhost=localhost,raddr=127.0.0.1,rport=60966,mid=<fd01d4dd-1def-1bc3-9a2a-5ede8f9dd...@designakeackson.info>,bayes=0.500000,autolearn=no > Nov 8 12:35:47 zed postfix/pickup[2485]: BCDF560EF: uid=65534 > from=<instant.checkm...@designakeackson.info> > Nov 8 12:35:47 zed postfix/cleanup[2517]: BCDF560EF: > message-id=<fd01d4dd-1def-1bc3-9a2a-5ede8f9dd...@designakeackson.info> > Nov 8 12:35:47 zed postfix/pipe[2518]: 2ABF060A6: to=<dani...@grinta.net>, > relay=spamassassin, delay=1.7, delays=0.24/0.01/0/1.4, dsn=2.0.0, status=sent > (delivered via spamassassin service) > Nov 8 12:35:47 zed postfix/qmgr[3850]: BCDF560EF: > from=<instant.checkm...@designakeackson.info>, size=10941, nrcpt=1 (queue > active) > Nov 8 12:35:47 zed postfix/qmgr[3850]: 2ABF060A6: removed > Nov 8 12:35:47 zed postfix/local[2522]: BCDF560EF: to=<dani...@grinta.net>, > relay=local, delay=0.02, delays=0/0.01/0/0.01, dsn=5.4.6, status=bounced > (mail forwarding loop for dani...@grinta.net) > Nov 8 12:35:47 zed postfix/cleanup[2517]: C0B0160EC: > message-id=<20121108123547.c0b016...@zed.grinta.net> > Nov 8 12:35:47 zed postfix/bounce[2523]: BCDF560EF: sender non-delivery > notification: C0B0160EC > Nov 8 12:35:47 zed postfix/qmgr[3850]: C0B0160EC: from=<>, size=12730, > nrcpt=1 (queue active) > Nov 8 12:35:47 zed postfix/qmgr[3850]: BCDF560EF: removed > Nov 8 12:35:52 zed postfix/smtp[2512]: C0B0160EC: host > eforward3.registrar-servers.com[209.105.246.196] said: 450 4.1.1 > <instant.checkm...@designakeackson.info>: Recipient address rejected: > unverified address: unknown user: "instant.checkm...@designakeackson.info" > (in reply to RCPT TO command) > Nov 8 12:35:52 zed postfix/smtp[2512]: C0B0160EC: host > eforward1.registrar-servers.com[69.160.33.82] refused to talk to me: 421 > 4.3.2 All server ports are busy > Nov 8 12:35:54 zed postfix/smtp[2512]: C0B0160EC: > to=<instant.checkm...@designakeackson.info>, > relay=eforward2.registrar-servers.com[209.105.246.195]:25, delay=7.2, > delays=0/0/7/0.17, dsn=4.1.1, status=deferred (host > eforward2.registrar-servers.com[209.105.246.195] said: 450 4.1.1 > <instant.checkm...@designakeackson.info>: Recipient address rejected: > unverified address: unknown user: "instant.checkm...@designakeackson.info" > (in reply to RCPT TO command)) > Nov 8 12:45:42 zed postfix/qmgr[3850]: C0B0160EC: from=<>, size=12730, > nrcpt=1 (queue active) > Nov 8 12:45:43 zed postfix/smtp[2566]: C0B0160EC: host > eforward3.registrar-servers.com[209.105.246.196] refused to talk to me: 421 > 4.3.2 All server ports are busy > Nov 8 12:46:05 zed postfix/smtp[2566]: C0B0160EC: host > eforward2.registrar-servers.com[209.105.246.195] said: 450 4.1.1 > <instant.checkm...@designakeackson.info>: Recipient address rejected: > unverified address: unknown user: "instant.checkm...@designakeackson.info" > (in reply to RCPT TO command) > Nov 8 12:46:06 zed postfix/smtp[2566]: C0B0160EC: host > eforward1.registrar-servers.com[69.160.33.82] refused to talk to me: 421 > 4.3.2 All server ports are busy > Nov 8 12:46:06 zed postfix/smtp[2566]: C0B0160EC: host > eforward4.registrar-servers.com[69.160.33.74] refused to talk to me: 421 > 4.3.2 All server ports are busy > Nov 8 12:46:06 zed postfix/smtp[2566]: C0B0160EC: > to=<instant.checkm...@designakeackson.info>, > relay=eforward5.registrar-servers.com[38.101.213.202]:25, delay=619, > delays=595/0.04/24/0, dsn=4.3.2, status=deferred (host > eforward5.registrar-servers.com[38.101.213.202] refused to talk to me: 421 > 4.3.2 All server ports are busy) My configuration: # postconf -n alias_database = hash:/etc/aliases alias_maps = hash:/etc/aliases allow_min_user = no append_dot_mydomain = no biff = no config_directory = /etc/postfix disable_vrfy_command = yes home_mailbox = Maildir/ inet_interfaces = all inet_protocols = ipv4 mailbox_command = /usr/lib/dovecot/dovecot-lda -f "$SENDER" -a "$RECIPIENT" mailbox_size_limit = 0 message_size_limit = 0 mydestination = grinta.net, zed, zed.grinta.net, localhost myhostname = zed.grinta.net mynetworks = 127.0.0.0/8 myorigin = /etc/mailname owner_request_special = no readme_directory = no recipient_delimiter = + relayhost = smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache smtpd_banner = $myhostname ESMTP smtpd_data_restrictions = reject_unauth_pipelining, permit smtpd_delay_reject = yes smtpd_helo_required = yes smtpd_recipient_restrictions = permit_sasl_authenticated reject_invalid_hostname reject_non_fqdn_hostname reject_non_fqdn_sender reject_non_fqdn_recipient reject_unknown_sender_domain reject_unknown_recipient_domain permit_mynetworks reject_unauth_destination reject_rbl_client zen.spamhaus.org reject_rbl_client bhnc.njabl.org reject_rbl_client dul.dnsbl.sorbs.net permit smtpd_sasl_auth_enable = yes smtpd_sasl_authenticated_header = yes smtpd_sasl_path = private/auth smtpd_sasl_type = dovecot smtpd_tls_auth_only = yes smtpd_tls_cert_file = /etc/postfix/postfix.cert smtpd_tls_key_file = /etc/postfix/postfix.key smtpd_tls_security_level = may smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache unknown_local_recipient_reject_code = 550 Thanks in advance for your help. Cheers, Daniele