Mailq overload due to relay mails from other domains

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Mailq overload due to relay mails from other domains

Postby Marcosebas » Mon Jul 29, 2019 6:31 pm

Dear All,

I am facing the following issue. I have a ZCS 8.8.9 fresh installation. However, today I am suffering a serious problem that is causing a delay in my ZCS to receive and send mails. My queue is full of mails from domains that are not part of my zimbra and sending to other domains too. I found this with mailq finding in a certain moment more than 30000 requests and in my anstipam system which is blocking all of them. Luckily, if not I would be blacklisted :D


I followed this wikis

1. Rejecting false "mail from" addresses:
2. Enforcing a match between FROM address and sasl username:

Also te postconf mynetworks is set with the networks part of my system.

This is my postconf sender restriction

Code: Select all

[zimbra@postfix ~]$ postconf | grep 'smtpd_sender_restrictions ='
smtpd_sender_restrictions = check_sender_access lmdb:/opt/zimbra/conf/postfix_reject_sender, check_sender_access regexp:/opt/zimbra/common/conf/, permit_mynetworks, reject_sender_login_mismatch, reject_unlisted_sender, reject_non_fqdn_helo_hostname, reject_non_fqdn_sender, reject_unknown_sender_domain, reject_unknown_reverse_client_hostname, reject_unknown_client_hostname, permit_sasl_authenticated, permit_tls_clientcerts, check_sender_access regexp:/opt/zimbra/common/conf/

These are my zimbra restrictions

Code: Select all

[zimbra@postfix ~]$ zmprov gacf | grep zimbraMtaRestriction 
zimbraMtaRestriction: reject_invalid_helo_hostname
zimbraMtaRestriction: reject_non_fqdn_helo_hostname
zimbraMtaRestriction: reject_non_fqdn_sender
zimbraMtaRestriction: reject_unknown_client_hostname
zimbraMtaRestriction: reject_unknown_helo_hostname
zimbraMtaRestriction: reject_unknown_reverse_client_hostname
zimbraMtaRestriction: reject_unknown_sender_domain
zimbraMtaRestriction: reject_rbl_client
zimbraMtaRestriction: reject_rbl_client
zimbraMtaRestriction: reject_rbl_client

In the admin console in global configuration > MTA all that rejects and RBLs are set:


Please, any guess, advise or help in how to stop this is appreciated.



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