Linux: Postfix – Parâmetros de configuração

Neste post compartilho alguns parâmetros necessários para tratar o número de tentativas de reenvio de e-mails.

Todos os parâmetros do postfix podem ser acessados neste link.

Exemplo de como localizar um parâmetro

#postconf -d | grep maximal_queue_lifetime

Exemplo de como alterar um parâmetro. O serviço deve ser reiniciado, após alteração.

#postconf -e 'maximal_queue_lifetime = 3d'
 
# cat /etc/postfix/main.cf

Temos 2 parâmetros que definem quanto tempo a mensagem fica na fila:

maximal_queue_lifetime (default: 5d)
Consider a message as undeliverable, when delivery fails with a temporary error, and the time in the queue has reached the maximal_queue_lifetime limit.
Time units: s (seconds), m (minutes), h (hours), d (days), w (weeks). The default time unit is d (days).
Specify 0 when mail delivery should be tried only once.

bounce_queue_lifetime (default: 5d)
Consider a bounce message as undeliverable, when delivery fails with a temporary error, and the time in the queue has reached the bounce_queue_lifetime limit. By default, this limit is the same as for regular mail.
Time units: s (seconds), m (minutes), h (hours), d (days), w (weeks). The default time unit is d (days).
Specify 0 when mail delivery should be tried only once.
This feature is available in Postfix 2.1 and later.

Estes 3 parâmetros definem o tempo de verificação da fila:

queue_run_delay (default: 300s)
The time between deferred queue scans by the queue manager; prior to Postfix 2.4 the default value was 1000s.
This parameter should be set less than or equal to $minimal_backoff_time. See also $maximal_backoff_time.
Time units: s (seconds), m (minutes), h (hours), d (days), w (weeks). The default time unit is s (seconds).

minimal_backoff_time (default: 300s)
The minimal time between attempts to deliver a deferred message; prior to Postfix 2.4 the default value was 1000s.
This parameter also limits the time an unreachable destination is kept in the short-term, in-memory, destination status cache.
This parameter should be set greater than or equal to $queue_run_delay. See also $maximal_backoff_time.
Time units: s (seconds), m (minutes), h (hours), d (days), w (weeks). The default time unit is s (seconds).

maximal_backoff_time (default: 4000s)
The maximal time between attempts to deliver a deferred message.
This parameter should be set to a value greater than or equal to $minimal_backoff_time. See also $queue_run_delay.
Time units: s (seconds), m (minutes), h (hours), d (days), w (weeks). The default time unit is s (seconds).