Install cyrus-admin by entering the following commands in the terminal:
sudo apt update sudo apt install cyrus-admin
Cyrus mail system - administration tools
This package provides the administrative tools for the Cyrus IMAPd suite. It contains the cyradm tool which can be used to administer both local and remote Cyrus mail systems. It also contains sieveshell and its deprecated cousin installsieve, which can be used to manage sieve scripts. . For more information, please see the cyrus-common package.