#MTAs
<virtual-mta ip1>
smtp-source-host 192.198.0.1 host.domain.tld
<domain *>
max-msg-rate 400/h
</domain>
</virtual-mta>
#DKIM Keys
domain-key key1,domain1.tld,/etc/pmta/keys/key1.domain.tld
domain-key key2,domain2.tld,/etc/pmta/keys/key2.domain.tld
domain-key key3,domain3.tld,/etc/pmta/keys/key3.domain.tld
#Specify the DKIM for specific Domain using Directive
<domain domain1.tld>
dkim-sign yes
smtp-hosts [127.0.0.1]:587
dkim-identity @domain1.tld
</domain>
<domain domain2.tld>
dkim-sign yes
smtp-hosts [127.0.0.1]:587
dkim-identity @domain2.tld
</domain>
<domain domain3.tld>
dkim-sign yes
smtp-hosts [127.0.0.1]:587
dkim-identity @domain3.tld
</domain>
#CALL PMTA POOL for Rotation
<virtual-mta-pool pmta-pool>
virtual-mta ip1
</virtual-mta-pool>