Summary
To change the retransmission time in Postfix, you need to modify the `main.cf` configuration file. The most relevant parameters are `transport_retry_time`, `minimal_backoff_time`, `maximal_backoff_time`, and `queue_run_delay`. `transport_retry_time` sets the time between attempts to a malfunctioning transport. The backoff times dictate the range of retry delays. Decreasing `queue_run_delay` makes Postfix retry more frequently, but can increase system load. If facing greylisting issues, consider whitelisting instead of solely adjusting Postfix settings. Understanding how these parameters interact is crucial for optimizing delivery. Be sure to test changes to avoid overloading the server. `delay_warning_time` affects delivery notifications, not retransmission itself.
Key findings
- main.cf Parameters: Configuration is primarily done through parameters in the `main.cf` file.
- transport_retry_time: Sets the time between attempts to a malfunctioning transport.
- Backoff and Queue Parameters: `minimal_backoff_time`, `maximal_backoff_time`, and `queue_run_delay` are key for retry configuration.
- Greylisting Alternative: For greylisting, whitelisting is a potential alternative to adjusting retry times.
Key considerations
- System Load: Reducing `queue_run_delay` can increase system load; test thoroughly.
- Parameter Interaction: Understanding the interplay of parameters is critical for effective tuning.
- Greylisting Handling: Address greylisting issues through appropriate methods, such as whitelisting.
- delay_warning_time: `delay_warning_time` influences notifications, not retry frequency.
What email marketers say
10 marketer opinions
To modify the retransmission time in Postfix, you primarily need to edit the `main.cf` configuration file. Several parameters influence retry behavior, including `transport_retry_time`, `minimal_backoff_time`, `maximal_backoff_time`, and `queue_run_delay`. Adjusting these parameters allows you to control how often Postfix attempts to resend emails and the range of the retry intervals. Be mindful of greylisting and server load when making changes.
Key opinions
- main.cf Configuration: The primary configuration file for adjusting retransmission settings is `main.cf`.
- Retry Parameters: Key parameters to modify include `transport_retry_time`, `minimal_backoff_time`, `maximal_backoff_time`, and `queue_run_delay`.
- Backoff Times: `minimal_backoff_time` and `maximal_backoff_time` control the range of delays for retries.
- Queue Run Delay: Decreasing `queue_run_delay` causes Postfix to retry more frequently.
Key considerations
- Greylisting: If dealing with greylisting, consider whitelisting or integrating with a greylisting daemon instead of solely adjusting Postfix.
- Server Load: Always test changes to ensure you do not overload the server.
- Parameter Impact: Understand the impact of each parameter to fine-tune Postfix's retry behavior effectively.
Marketer view
Email marketer from ServerFault answers that you can tune Postfix retry settings by adjusting `minimal_backoff_time` (default: 100s), `maximal_backoff_time` (default: 4000s), and `queue_run_delay` (default: 300s). He suggests experimenting with these values based on your specific needs, such as reducing the delay for local network issues.
10 Nov 2023 - ServerFault
Marketer view
Marketer from Email Geeks shares that you can set the retransmission time in Postfix by modifying the `transport_retry_time` setting in the `main.cf` file. The default time unit is seconds, but can be set in seconds (s), minutes (m), hours (h), days (d), weeks (w).
27 Sep 2022 - Email Geeks
What the experts say
1 expert opinions
Tuning Postfix involves understanding how parameters like `minimal_backoff_time`, `maximal_backoff_time`, and `queue_run_delay` interact to optimize email delivery.
Key opinions
- Parameter Understanding: A key finding is the importance of understanding the effect of the parameters.
- Parameter Interaction: The parameters need to be understood how they work together.
Key considerations
- Optimizing Delivery: Understanding parameter relationships is key to optimizing delivery.
Expert view
Expert from Word to the Wise explains that when tuning Postfix, it is important to understand the effect of parameters such as `minimal_backoff_time`, `maximal_backoff_time`, and `queue_run_delay`. Understanding how these work together is key to optimizing delivery.
6 Jun 2024 - Word to the Wise
What the documentation says
4 technical articles
Postfix documentation outlines several parameters that control retransmission behavior. `transport_retry_time` sets the interval between attempts to contact a malfunctioning transport. `minimal_backoff_time`, `maximal_backoff_time`, and `queue_run_delay` should be configured within the `main.cf` file to adjust retry intervals. Lowering `queue_run_delay` increases retry frequency but can increase system load. `delay_warning_time` is related to delivery status notifications, not retry settings.
Key findings
- transport_retry_time: Specifies the time between attempts to contact a malfunctioning transport; default is 60s.
- Retry Parameters: `minimal_backoff_time`, `maximal_backoff_time`, and `queue_run_delay` control retry intervals.
- queue_run_delay: Defines the time between deferred queue scans; lowering it increases retry frequency.
- Configuration File: Parameters are configured in the `main.cf` file.
Key considerations
- System Load: Lowering `queue_run_delay` increases system load.
- delay_warning_time: `delay_warning_time` is for notifications, not retry configuration.
Technical article
Documentation from Postfix.org explains that the `transport_retry_time` parameter specifies the time between attempts by the Postfix queue manager to contact a malfunctioning message delivery transport. Time units can be specified in seconds (s), minutes (m), hours (h), days (d), or weeks (w). The default is 60s.
20 Dec 2021 - Postfix.org
Technical article
Documentation from Postfix.org details that the parameter `delay_warning_time` determines when Postfix will send a warning message to the sender about a delayed email. This is not a retry setting, but it is related to the email's delivery status and can be helpful for monitoring delivery issues.
10 Jun 2022 - Postfix.org
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