Is the order of application of forwarding rules and fitering rules documented?

chrisisbd

Member
Jan 6, 2011
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0
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As per the subject, is there anywhere in the cPanel documentation that specifies the order in which the various filtering and forwarding rules are applied? There are a few hints in places, for example in the forwarding section it says "Warning: Forwarding a domain's email will override the default address for that domain" but this is only one little bit of a whole sequence of things that cPanel configuration might do to an incoming E-Mail.

It would be *incredibly* useful to know the order of application of:-
E-Mail account forwarders
E-Mail domain forwarders
Account Level Filtering
User Level Filtering
When an E-Mail will get sent to the Default Address

In particular whether forwarding is applied before or after filtering is of great importance when setting these up.
 

chrisisbd

Member
Jan 6, 2011
8
0
51
I have found the answer I needed to this question by reading the documentation for the underlying Exim filtering.

Basically *all* the filter rules are applied and any that match will do the relevant action. So having one rule that says "no further processing" and another that delivers the mail *will* deliver the mail even if both match. It's only if no rule that delivers the mail matches that the "no further processing" rule takes effect, it just means that the E-Mail isn't passed on for further processing after the filter rules have *all* been applied.

It's somewhat counter-intuitive in the sense that one expects the rules to be applied in order somehow and that once an E-Mail has been dumped (for example) nothing further will happen, but that's not the way it works. A rule that does "Discard Message" is ineffective if any other rule matches the same message.

This really is the answer to all my other questions too really, once one realises the way the underlying filters work then it does make sense, even though it makes them a bit more difficult to use than if they were applied sequentially.