apt install ssmtp
Konfig unter /etc/ssmtp/ssmtp.conf bearbeiten
mailhub=relay.domain.local:25
#useSTARTTLS=YES
#AuthUser=username-here
#AuthPass=password-here
#TLS_CA_File=/etc/pki/tls/certs/ca-bundle.crt
echo "Test message from Linux server using ssmtp" | sudo ssmtp -vvv dummy@domain.local
printf "Subject: Test\n\nTest message from $(hostname)" | ssmtp -vvv dummy@domain.local