Re: rejecting mails to unknown domains or recipients

Message --- On Wednesday, November 23rd, 2022 at 17:16, Viktor Dukhovni wrote: > > On 23 Nov 2022, at 10:58 am, Juan Smitt Jr juan.smitt...@proton.me wrote: > > > > I'm just wondering, what's the risk in adding > > 'reject_unknown_recipient_domai

rejecting mails to unknown domains or recipients

Hi, I'm just wondering, what's the risk in adding 'reject_unknown_recipient_domain' and 'reject_unverified_recipient' to the config. I have tried all the different kind of default installs on Ubuntu 20 and none of them contains these settings. Is that because of the packager just didn't want

check remote auth

Hi, We frequently have to create relay rules to remote smtp servers using username and password. Before we create the confguration, we always check the availability of the remote server and port and we also try to check if the provided username and password are valid. For this we are using o

Re: understanding empty message-id header

2 at 13:17, Markus Schönhaber wrote: > 11.11.22, 13:02 +0100, Juan Smitt Jr: > > > Can you help me please understand the "message-id" header? > > > > Sometimes it's missing from the emails and i.e. gmail rejects these emails. > > > > Is it adde

understanding empty message-id header

Hello, Can you help me please understand the "message-id" header? Sometimes it's missing from the emails and i.e. gmail rejects these emails. Is it added by the email client (application) or is it added by postfix? Thank you!

time spent in active queue

Hi, What can we check/tune if there are ~35K mails in the active queue (stress test is being performed) and a mail spends ~4m in the active queue? Example: 2022-10-13 07:54:05.823323+00:00 postfix/qmgr ... (queue active) (no log entries here) 2022-10-13 07:58:12.308448+00:00 postfix/smtp ... rel

Re: response time to the client

írta (időpont: 2022. okt. 12., Sze, 16:25): > > On 12.10.22 12:36, juan smitt wrote: > >The clients are very sensitive to the mail service's response time (we > >can't do anything with that). > > I have ancountered this issue too. > > >According to this examp

response time to the client

Hi, The clients are very sensitive to the mail service's response time (we can't do anything with that). According to this example, is it true that the client considers the email delivered when we see the "(queue active)" entry in the log whatever happens to the mail later? Can we calculate the

monitoring the effectiveness of smtpd processes

Hi, How can one directly monitor the effectiveness of the increased number of Postfix SMTP server processes? (https://www.postfix.org/STRESS_README.html) Is it true that this scales up dynamically until the limit, which means I can monitor it indirectly by counting the number of processes (and a

regulating legitimate mail traffic

Hi, It's written in the doc that "smtpd_client_connection_count_limit" is about the number of simultaneous connections from a client, but it's also written that "It must not be used to regulate legitimate mail traffic." If this is not the way, then how can one regulate the simultaneous connectio

comments in config files

Hi, Can you please confirm that it won't cause any problem if we put comments at the end of config lines? Example: file: /etc/postfix/virtual postmaster postmas...@example.com # this is a comment We need to know this because of automation reasons. Thanks!

DNS issue in the multi instance

Hi, There is a postfix server (v3.4.13) with a multi instance (master.cf): #servicetype private unpriv chroot wakeup maxproc command 127.0.0.1:30004 inet n- n - - smtpd The master instance can send email to anywhere on the internet but the multi inst

dropping emails

Hi, We have some rules to drop emails sent to certain recipients. main.cf: smtpd_recipient_restrictions = check_recipient_access regexp:/etc/postfix/custom_recipient_blacklist_regex custom_recipient_blacklist_regex: /^du...@whatever.fqdn$/ discard The problem is when an email has more recipie

Re: matching envelope sender and a certain header

Thanks everyone for the great ideas. I'll try the 'envfrom' tomorrow. Wietse Venema ezt írta (időpont: 2022. máj. 23., H, 15:46): > > juan smitt: > > Hi, > > > > > > We got a request to match the envelope sender with a certain mail > > heade

matching envelope sender and a certain header

Hi, We got a request to match the envelope sender with a certain mail header (i.e. X-Something) on our relay servers for every outbound mails and reject the email if the sender and the value of this header don't match. It's also possible for a sender to have more than one valid X-Something value