I get a VAST number of what appears to be requests for fake email address.
ime, this is just "normal" Internet mail behavior, and has been for about a year, or more.
Here's a summary for an IMGate where the predominant policy is "reject unknown recipient", plus a little bit of DISCARDing msgs with known virus strings, and some attachments.
Postfix log summaries for Aug 6 (all 24 hours)
Grand Totals ------------ messages
266659 received
294677 delivered
0 forwarded
102 deferred (111 deferrals)
14 bounced
381618 rejected (56%)
373645 reject warningsOf the 386k rejected, 366K were unknown recipient. Yawn, it's like that on every IMGate I admin.
If this client were to turn on all the usual IMGate policies, the reject rate would very probably be 80% to 90%.
You can't prevent "unknown recipients" because it comes from 10's of 1000's of IPs. Your best tactic is to reject after RCTP TO: so that the costs to your MX and bandwidth is minimized.
The worst tactic is to let all of that hit your Imail server, which we know is not efficient in rejecting unknown recipients vs the efficiency of IMGate, such that if the above rejected unknown recipient volume were allowed to hit my client's Imail server, his Imail would be dead in minutes, rather than humming along now with very low utilization.
The absolute worst tactic is Imail nobody@ alias. Not only does all of that crap hit IMail, Imail actually swallows every last byte of it, maximizing your losses in Imail resources and your bandwidth.
Len
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http://IMGate.MEIway.com : free anti-spam gateway, runs on 1000's of sites
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"Our enemies are innovative and resourceful, and so are we,'' shrub said. ``They never stop thinking about new ways to harm our country and our people, and neither do we." Aug_04
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