[exim] Diverting sub-domain to ;blackhole:

Wanting to divert sub-domain xyz.domain.com to a :blackhole: I first
tried in Rewrite to change the envelope address with

*@xyz.domain.com :blackhole: T

but Exim rejected that coding.

I tried again in Routers doing things like:

weg:
    driver     = redirect
    data       = xyz.domain.com
    transport  = :blackhole:

'Transport' is not allowed. The Exim 4.71 PDF fails to explain the
syntax. Google can't find anything illustrative.

I know I can delete the MX entry for xyz.domain.com and create lots of
bounces but I wanted to simply drop the expected deluge of emails to
that sub-domain.

Although I have found a workable substitute, shown below, does anyone
know how to divert an entire sub-domain to :blackhole: or /dev/null ?

--------------

REWRITE

    *@xyz.domain.com            delete@???  T

/etc/aliases

    delete:   :blackhole:

-------------

One of the resulting Exim log file lines is

> 2010-02-11 21:44:19 1Nfgpf-0008GP-K8 => :blackhole: <delete@???> R=system_aliases

I assume R= means Router and the 'system_aliases' is a predefined class
of routers. How does one set-up a 'system_aliases' router to deliver
sub-domain emails to :blackhole: ?

Regards,

Paul.

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