MailScanner causes SpamAssassin rules to firing inconsistently

Mark Sapiro mark at
Thu Nov 5 18:44:14 UTC 2015

On 11/05/2015 09:51 AM, Wolfgang Baudler wrote:

> Not sure what you mean with normal messages being present. There is always
> a lot of activity on that server, mostly spam, but also some ham messages
> present most of the time. "Max Children" is set to 5, but testing with
> only one instance of MailScanner resulted in the same behavior also.

By 'normal', I mean't not errors or warnings. I mean if you consider two
messages, one that fires and one that doesn't, if you look at all the
MTA and MailScanner log messages relevant to the processing of those two
messages, are the log messages the same or is there some difference
between the two sets.

> If there is only one instance of MailScanner running it still processes
> messages in batches, right? Is it possible that that it gets confused in
> that process and is mixing the results of different messages scanned in
> the same batch? Still doesn't explain why internal messages always fire
> correctly.

Yes, even with only one child, processing is still in batches. If there
is some evidence (added headers) in the message that doesn't fire that
spamassassin was invoked on that message, I don't see how that's an issue.

OTOH, if there is no evidence that spamassassin was invoked on the
message at all, then we are looking at 'why does MailScanner sometimes
skip spamassassin' as opposed to 'why does spamassassin sometimes behave
differently'. The former could be a rule set.

Years ago, with MailScanner and Postfix, I would see occasional message
duplication with multiple children, so I've been running with one child
process ever since, but that doesn't seem relevant

Mark Sapiro <mark at>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan

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