Install couriergrey by entering the following commands in the terminal:
sudo apt update sudo apt install couriergrey
Description:
Mail filter interface of Courier-MTA to support greylisting
Couriergrey implements the mail filter interface of Courier MTA to support the greylist filtering method. . The software supports the IPv6 protocol, and is easy to use.
Homepage: http://couriergrey.com/
Version: 0.3.2-5build2
Section: universe/net