Knowledge base

Which login it was submitted under

rcvSmtpUser
Which of the submitters exactly

The name of the account under which authentication took place.

It is not written by default — the field has to be named in record-fields. The field set is defined in the accounting block, and fields are worth adding deliberately: there are as many delivery records as delivered recipients, and every extra column is multiplied by that volume.

Here a login is created for each sending pair, plus one more — the shared pool login: this field shows which of them submitted the message.

The main trap is expecting the field from the star. The star gives only the default fields, and this field is not among them: until it is named in record-fields, the file has no such column at all.
What the Hub does. It neither reads nor requests it: this field is not in the set the Hub specifies in record-fields — neither in the webhook nor in the accounting file on the node. If it is needed, the field has to be added there explicitly.
Recommended values

Where the field exists and whether the star includes it:

Record type In the star
d — delivery no
b — bounce no
t — temporary failure no
r — reception no

In a shared file an empty value comes in two kinds: the line has no data — or the field is not selected for its record type.

The record types with this field and the default set markers come from the manual (§ 12.2.1, § 12.2.2, § 12.2.3, § 12.2.5); a list without the star replaces the set — § 3.3.11.12. The table is ours.
Example configuration
<acct-file /var/log/pmta/acct.csv>
    record-fields d *, rcvSmtpUser</acct-file>
The star is the default fields, and rcvSmtpUser is added to them; for other record types the line is repeated with its own letter.
yellow — — directive names, blue — blocks. They are highlighted the same way in the text of the card.
Compatibility
PowerMTA 6.0
described in the manual of this version · platform: any
The vendor does not state the first version for every directive — there is no note here. The name also appears in the 5.0 edition of the manual.
How to check on the node
Check whether the column is in the latest accounting file:
head -1 "$(ls -t /var/log/pmta/acct-*.csv | head -1)" | tr -d '\r' | tr ',' '\n' | grep -n '^rcvSmtpUser$'
The line number in the output is the column number in the file; empty means the field is not selected for any record type in this file.
In the Hub
Cost of a mistake
safe: a wrong value breaks nothing