cat > /etc/opendkim.conf<<EOF
UserID                  opendkim:opendkim
UMask                   022
Mode                    sv
PidFile                 /var/run/opendkim/opendkim.pid
Canonicalization        relaxed/relaxed
TemporaryDirectory      /var/tmp
ExternalIgnoreList      refile:/etc/opendkim/TrustedHosts
InternalHosts           refile:/etc/opendkim/TrustedHosts
KeyTable                refile:/etc/opendkim/KeyTable
SigningTable            refile:/etc/opendkim/SigningTable
MinimumKeyBits          1024
Socket                  inet:8891
LogWhy                  Yes
Syslog                  Yes
SyslogSuccess           Yes
EOF

mkdir -p /etc/opendkim/keys/`hostname -f`
opendkim-genkey -D /etc/opendkim/keys/`hostname -f`/ -d `hostname -f` -s default

#chown opendkim:opendkim -R /etc/opendkim/
#chmod -R 700 /etc/opendkim

echo "default._domainkey.`hostname -f` `hostname -f`:default:/etc/opendkim/keys/`hostname -f`/default.private" >> /etc/opendkim/KeyTable
echo "*@`hostname -f` default._domainkey.`hostname -f`" >> /etc/opendkim/SigningTable
echo "localhost" >> /etc/opendkim/TrustedHosts
echo "`hostname -f`" >> /etc/opendkim/TrustedHosts
cat >> /etc/postfix/main.cf<<EOF

#DKIM
milter_default_action = accept
milter_protocol = 2
smtpd_milters = inet:8891
non_smtpd_milters = inet:8891
EOF

#service opendkim start
#service postfix restart
cp /etc/opendkim/keys/`hostname -f`/default.txt /root/`hostname -f`-dkim-signature_default.txt

echo "open '/root/`hostname -f`-dkim-signature_default.txt', then add the TXT record to you DNS resolution system."