OK this is very weird.
I am running IMail 8.10 and am seeing the following. There is a
secondary MX record for one of the domains that I service. Someone seems
to be sending to it directly and so it sends me a lot of mail for this
domain (this is not a problem in my mind). The problem is that the SMTP
service stops accepting mail from this (and only this IP address) at
random times. It can work for hours and then fail and the next time I
restart the service it will work for minutes, completely unpredictable.
I have done a packet trace at my end and I see:
Them sending a SYN
I send and ACK
They send an ACK
Then I send a FIN
So we never get to the banner being sent out or the helo coming in.
There is nothing in the log even with debug and verbose turned on.
>From that point on SMTP will not accept a connection from that IP
address. But, it gets better, all other IPs can connect to the SMTP
server and still get their mail through. If the other ISP uses another
machine in the same IP block that machine can connect no problem.
I have increased the SMTP setting for Delay between recipients to 500
milliseconds but this seems to have no effect.
This is a dedicated machine to IMail.
Does anyone have any ideas on what this might be and how to fix it?
Goran Jovanovic
The LAN Shoppe
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