SPF is configured entirely in DNS—PowerMTA only needs to send from IPs listed in your SPF record:
<domain *> dkim-sign yes dkim-signature dkim dkim-identity mail.your-domain.com dkim-key-file /etc/pmta/dkim/your-domain.com.pem dkim-selector your-dkim-selector dkim-headers "From:Subject:To:Date" </domain>
<domain *> dkim-sign yes dkim-identity @mydomain.com dkim-private-key-file /etc/pmta/keys/mykey.pem spf-envelope-from mydomain.com </domain>
# Multi-VMTA hot configuration example virtual-mta pmta-newsletter-pool smtp-source-host 192.168.1.10 newsletter1.example.com smtp-source-host 192.168.1.11 newsletter2.example.com max-smtp-msg-rate 10000/h sample powermta configuration file hot
: Ensure that every IP listed in your smtp-source-ip directives accurately resolves back to the host-name listed within that same Virtual MTA block. If you need to adjust this template further, let me know: How many dedicated IP addresses you are using? What average volume of email you plan to send per hour?
A "hot" IP configuration must still respect the architectural limits of major inbox providers. Aggressive multi-connection delivery will trigger rate-limiting errors (e.g., Gmail's "421 4.7.0" or Yahoo's TS series errors).
In PowerMTA (PMTA), a "hot" configuration refers to a setup optimized for high-throughput delivery hot-standby/disaster recovery SPF is configured entirely in DNS—PowerMTA only needs
: Specifies the absolute path where PMTA will look for new message files. virtual-mta : Assigns the mail dropped in this folder to a specific VirtualMTA (IP pool and domain settings) for delivery. scan-interval
<domain *> max-smtp-out 20 queue-size 2000 max-message-size 10M use-remote-queue true </domain>
: Sets delivery limits for major ISPs (like Gmail or Yahoo) to avoid being flagged for spamming. Authentication : Implements to verify sender identity. Throttling & Rates A "hot" IP configuration must still respect the
: Supports high connection counts and requires TLS. The use-starttls yes directive ensures data privacy, which impacts sender reputation.
ISPs have different throttles. Sending 1000 emails per minute to a small ISP will trigger blacklisting. Using specific rules for major providers helps manage your reputation and ensure inbox placement 1.2.5 . 3. max-smtp-out