Exim

Basic MTA (Mail Transfer Agent)

The configuration can be modified in /etc/exim4/update-exim4.conf.conf. These lines need to be modified:

dc_eximconfig_configtype='satellite'
dc_other_hostnames='<your hostname>'
dc_readhost='<your domainname>'
dc_smarthost='<your mailserver>'
dc_hide_mailname='true'

Then run update-exim4.conf. This will put the final config in /etc/exim4/conf.d

exim -bt user@domain.tld

Show how mail to user@domain.tld will be routed