log-connections no log-commands no log-data no log-resolution no
: Reduces the time dead or deferred mail sits in your queue. For hot traffic, keeping transient mail in the spool for more than 48 hours wastes server resources.
To maintain a "hot" yet safe sending environment, you must implement granular rate limiting for specific domains. A common strategy involves setting a conservative global default while allowing higher throughput for trusted domains. Sample Value max-msg-rate Limits total messages per minute/hour max-conn-rate Limits new connection attempts per minute max-smtp-out Maximum concurrent outbound connections max-msg-per-connection Messages sent before closing a session Specialized Domain Handling
The "hot" configuration above includes several moving parts, but delivering email is simple: follow the receiver's rules. Here is how to tune the key limits for major ISPs: sample powermta configuration file hot
If these are new IPs, do not start with a hot config. You will be blocked.
# Define your local IPs as Virtual MTAs smtp-source-host 192.168.1.10 ://example.com smtp-source-host 192.168.1.11 ://example.com
<domain yahoo.com> max-msg-rate 30/h max-connect-rate 3/m retry-after 4h max-smtp-out 5 A common strategy involves setting a conservative global
<domain gmail.com> max-smtp-out 10 max-connect-rate 2/m max-msg-per-connection 50 max-msg-rate 200/h retry-after 5m log-connections yes </domain>
cp /etc/pmta/pmta.conf /etc/pmta/pmta.conf.bak
Here's a working template with "hot" settings ready for tuning: You will be blocked
I’ve put together a that focuses on three critical pillars:
run-as root smtp-name default-mta.yourdomain.com postmaster postmaster@yourdomain.com