Documentation
Transport rules
Transport rules let administrators modify incoming and outgoing mail on the server, before it is delivered or placed in the queue. When they apply Rules take ef…
Transport rules let administrators modify incoming and outgoing mail on the server, before it is delivered or placed in the queue.
When they apply
Rules take effect after the raw MIME blob has been stored, but before the sent copy is created and before the message is delivered locally or remotely. Changes therefore reach every recipient as well as the sent copy.
Conditions
| Field | Meaning |
|---|---|
from |
Sender address |
to |
Recipient address |
subject |
Subject line |
body |
Message text |
any |
Every message |
| Comparison | Meaning |
|---|---|
contains |
contains |
equals |
is equal to |
starts_with |
begins with |
ends_with |
ends with |
Regular-expression comparisons are deliberately not supported, to rule out ReDoS attacks.
Actions
| Action | Value |
|---|---|
add_header |
A header line, for example X-Custom: yes |
prepend_subject |
Text placed before the subject |
append_disclaimer |
Disclaimer text appended to the text part |
Order
Rules are evaluated by descending priority. Several rules may apply to the same message in sequence.
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