Powermta Configuration File Hot !exclusive!: Sample

max-msg-per-connection : Keeps a single connection open for up to 1000 messages, reducing the TCP handshake overhead significantly.

In the old days, people just sent mail from the server IP. In modern PowerMTA "hot" setups, we use .

# Virtual MTA for a specific IP smtp-source-ip 1.2.3.4 host-name ://yourdomain.com domain-key selector1, yourdomain.com, /etc/pmta/dkim.private.key # Virtual MTA Pool for load balancing multiple IPs virtual-mta vmta1 virtual-mta vmta2 Use code with caution. Copied to clipboard 4. Domain Directives (Rate Limiting)

cold-virtual-mta vmta-cold-2 <domain *> max-cold-virtual-mta-msg 500/day</domain> </virtual-mta> sample powermta configuration file hot

A PowerMTA (PMTA) configuration file, typically located at /etc/pmta/config

# TLS settings tls_cert_file = /path/to/tls_cert.pem tls_key_file = /path/to/tls_key.pem

max-deliveries-per-minute 500 max-deliveries-per-connection 5 retry-window 1h max-msg-per-connection : Keeps a single connection open for

<schedule 22-06> set max-smtp-out 50 set throttle-smtp-out 10000 </schedule>

: Ensures delivery does not fail if the receiving server lacks valid SSL/TLS certificates. Maintenance Tips for Hot Configurations

; Virtual MTA (vMTAs) for IP/pool separation — create two pools: warm and hot virtual-mta hot-pool # Virtual MTA for a specific IP smtp-source-ip 1

# Logging log_level = 3 log_file = /var/log/powermta.log

Below is a sample PowerMTA configuration file that demonstrates some of the key settings and features:

spool-dir /var/spool/pmta log-file /var/log/pmta/pmta.log