Postgrey (Re: impersonating Juan, a quick test)

Punk punks at
Mon Jul 15 12:20:13 PDT 2019

On Sun, 14 Jul 2019 18:30:01 -0700
Greg Newby <gbnewby at> wrote:

> In case this helps: Just yesterday I sent a longish message about the server setup for the system that is hosting this cypherpunks@ list.

	Yes! Thanks for sharing that info. I found it pretty interesting. 

> 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.

	I don't get any bounce. What happens is, I send a message (using claws mail) and it doesn't make it to the list. I know because I don't a copy of my own message. So I resend after a couple of minutes. Nothing. I resend again after a few more minutes. Nothing. Sometimes the third try works. Sometimes I need to resend one more time. After succesufully sending one message, I can send more messages without having to re-try. It seems as if some sort of filter changes status to "open" after being hit with a few messages in a row. But after some time (a few hours?) it goes back to "closed". (But ocasionally messages will get through at the first try.)

> 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.

	This one took five tries.

	(I'm sending you a copy of the original message to your address) 

	If you can easily find something in the postgrey logs that would be great but if it's something more complex requiring more effort then don't worry. Seems like I'm the only one having this issue so it's not a big deal. 

> Best,
>  Greg

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