Sample Powermta Configuration File Hot ~upd~ Jun 2026

The most common mistake is setting max-msg-rate unlimited . Major ISPs (Gmail, Outlook, Yahoo) will block you if you send too fast from a new IP.

smtp-timeout 60s connection-timeout 30s read-timeout 60s write-timeout 60s dns-timeout 10s

relay listen 127.0.0.1:2525 auth plain auth-login auth-secret /etc/pmta/auth.secret allow-mail-from *@yourmaindomain.com allow-recipient @ route-to-vmta main-sender sample powermta configuration file hot

retry-intervals 10m,30m,1h,3h,6h,12h,24h max-delivery-attempts 10 soft-bounce-action delayed hard-bounce-action bounce

<source 0/0> # Matches all other IPs always-allow-relaying no # Reject relaying unless authenticated process-x-virtual-mta yes max-message-size 10485760 smtp-service yes allow-unencrypted-plain-auth no # Reject plain-text passwords over unencrypted channels default-virtual-mta main-pool # Fallback VMTA if none selected </source> The most common mistake is setting max-msg-rate unlimited

# ########################################################### # PowerMTA High-Performance Configuration (The "Hot" Setup) # ########################################################### # --- 1. IP and Networking --- # Define the IP addresses you will use for sending smtp-source-host 1.2.3.4 ://yourdomain.com smtp-source-host 1.2.3.5 ://yourdomain.com # --- 2. Postmaster and Logging --- postmaster postmaster@yourdomain.com log-errors yes log-transfers yes log-commands no record-header-names X-Job,To,Message-ID # --- 3. Bounce and FBL Processing (The "Hot" Part) --- enabled yes include-with-category-codes yes # Global bounce expiration replace-unnamed-bounce-handler yes type delayed max-delay 4d # --- 4. Virtual MTAs (IP Pools) --- smtp-source-host 1.2.3.4 ://yourdomain.com host-name ://yourdomain.com smtp-source-host 1.2.3.5 ://yourdomain.com host-name ://yourdomain.com # --- 5. Domain Directives (Deliverability Tuning) --- # Default settings for all domains max-smtp-out 20 # Max simultaneous connections max-msg-rate 500/h # Warm-up rate (increase as reputation grows) retry-after 30m # How long to wait before retrying a soft bounce bounce-after 4d # Give up after 4 days dkim-sign yes dkim-algorithm rsa-sha256 # Specific Tuning for Gmail (The "Golden" Settings) max-smtp-out 100 max-msg-per-connection 50 smtp-greeting-timeout 5m idle-timeout 1m # Specific Tuning for Yahoo/AOL max-smtp-out 40 max-msg-per-connection 20 max-msg-rate 1000/h # --- 6. Security and Authentication --- http-mgmt-port 8080 http-access 127.0.0.1 monitor http-access 192.168.1.100 admin # Your Management IP always-allow-relaying yes process-x-job yes log-connections no log-commands no smtp-service yes Use code with caution. Why This Configuration is "Hot" 1. Granular Domain Directives

<source 127.0.0.1> always-allow-relaying yes # Allows relaying without auth from this IP process-x-virtual-mta yes # Allows selection of a Virtual MTA via XMTA header max-message-size 0 # No message size cap (0 = unlimited) smtp-service yes # Enable SMTP service on this IP allow-mailmerge yes # Enable PowerMTA's MailMerge feature for efficiency </source> IP and Networking --- # Define the IP

vmta main-sender auto-warmup true pool pool-high-volume dkim-signature "main" # See DKIM section below always-allow-vmta-domain true max-smtp-out 200 queue-type shared

: This is set to 10000 in the example to handle large queues. It determines how many SMTP connections PMTA can have open concurrently.