sed -i "s/REPLACE_Domain_ECALPER/${mail_domain}/g" /etc/opendkim.conf
sed -i "s/REPLACE_Selector_ECALPER/${dkim_selector}/g" /etc/opendkim.conf
sed -i "s/REPLACE_myhostname_ECALPER/$(hostname -f)/g" /etc/postfix/main.cf
sed -i "s/REPLACE_Domain_ECALPER/${mail_domain}/g" /etc/opendkim.conf
sed -i "s/REPLACE_Selector_ECALPER/${dkim_selector}/g" /etc/opendkim.conf
sed -i "s/REPLACE_myhostname_ECALPER/$(hostname -f)/g" /etc/postfix/main.cf