Postgrey (Re: impersonating Juan, a quick test)

Razer g2s at
Mon Jul 15 13:40:13 PDT 2019

On July 14, 2019 6:30:01 PM PDT, Greg Newby <gbnewby at> wrote:
>On Sun, Jul 14, 2019 at 07:43:19PM -0300, Punk wrote:
>> 	sorry for the duplicated posts. So while on the topic of email
>systems, there's been some change somewhere  - either or the
>list's server I'd guess - and since a month or so I have to send the
>same message multiple times (around 4 usually) until it actually gets
>In case this helps: Just yesterday I sent a longish message about the
>server setup for the system that is hosting this cypherpunks@ list.
>One of the components is postgrey (which I misspelled postgray). When a
>message arrives from an unknown host, Postfix rejects it with a message
>to try again later. This is extremely effective against hit-and-run
>spam and similar annoyances.
>I've found that there are lots of organizations that do not follow the
>RFCs for email properly, and do not try again. Lots of banks and
>ecommerce sites seem to write their own mail transport agent (MTA), and
>do not try again after getting the postgrey message.
>It seems possible this is what's happening to your messages. If your
>service is using an MTA that doesn't try again - or if it tries again,
>but from a different IP address - the message might not get through.
>You should get a bounce saying it couldn't be delivered (anywhere from
>30 minutes to 7 days later), but organizations that write their own
>MTAs might not handle error delivery that well, either.
>If you have a message that doesn't seem to get posted, please forward
>me the message and I'll mine the logs to see what happened. There are
>plenty of other possibilities that might cause this, but postgrey is
>one that we can investigate easily enough.
> Greg

I was blacklisted without notification a decade ago. A listserv admin contacted me and told me *some* (but not all) of my contributions (I call them that anyway...) bounced going to some addresses when redistributed by the list.

-- Rr
Sent from my Android device with K-9 Mail. Please excuse my brevity.

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