Sthu Pous a écrit : > Good day. > > I do not from whence (I see no client connection from /var/log/mail.log) the > weird letters come, but I see them as: > > postfix/qmgr[2589]: 4B59323B3A: from=<>, size=3751, nrcpt=1 (queue active) > > latter then they are sent: > > postfix/smtp[8888]: 4B59323B3A: to=<x...@yyyy.zz>, relay=none, delay=147396, > delays=147365/0.07/31/0, dsn=4.4.1, status=deferred (connect to > yyyy.zz[aaa.bbb.ccc.dd]:25: Connection timed out) >
if you don't see a connect, then it is a bounce generated by your server. to see what message caused the bounce, grep for <x...@yyyy.zz>. > So, can You please help me with the following, how I can: > > - investigate (debug?) from whence it comes? and > > - filter/ban it? > if it's a bounce generated by your server, you need to find out what was bounced, and block the "original" messages. Otherwise, don't block mail from "<>" in general, because this is how your users get bounces. you can block some backscatter though. see the BACKSCATTER README. > > Thank You for Your time.
