[MM3-users] How to identify the exact reason behind the shunting of the mails ?

Hi Team,

       I am currently running Mailman 3 with version 3.3.1 and in-built

postfix version 2.10.1-6 on RHEL 7.5 with PostgreSQL 11.7 version with default values. I am almost running 2000 lists with 128 GB RAM and 24 Cores on a single VM and on which all the mailman 3 components are running. I have been running this setup in production for the past 2 years and 6 months.

      From the beginning of the above setup until recent days, I

observed a few mails moving to the shunt queue now and then. But from recent days it is observed that many mails are moving to the shunt queue.

      I browsed many websites but I could not get a proper resolution

for identifying the exact reason behind the shunting of the mails. Because of which I had been asking the user to resend the mails instead of suggesting the user regarding the issue properly.

      I in fact used the command "mailman qfile <filename.pck>" even

then I don't understand what might be wrong with the mail composition. Most of the time I see *unknown-8bit* in To or CC fields and I don't know if it is linked with the reason for shunting or not and I don't get any clue from it either.

     Is there any chance to find out the reason for shunting of the

mails through any means ?

-- Thanks & Regards, Shashi Kanth.K 9052671936