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Re: Yahoo! Mail Issue
From: Christopher Balmain <chris () team dcsi net au>
Date: Tue, 12 Apr 2011 17:04:56 +1000

We had a lot of issues delivering mail to yahoo.com.sg about a year ago
(just the .sg domain, plain .com was fine). Could establish connection
but it'd die halfway through transferring mail. A static route to drop
the MTU (for their subnet only) to 1000 fixed the problem right up.

Not sure if pmtud was/is broken or what.

- Chris

On Tue, 2011-04-12 at 15:29 +1000, Nathanael C. Cariaga wrote:
Thanks anyway.  I just find this issue intriguing since not all Yahoo 
mail accounts are affected.  In addition, incoming mails from other 
domain doesn't seem to be affected.  That is why I want to check if it 
is a network issue :)


On 4/12/2011 1:17 PM, Matthew Petach wrote:
On Mon, Apr 11, 2011 at 9:54 PM, Brielle Bruns<bruns () 2mbit com>  wrote:
On 4/11/11 10:47 PM, Matthew Petach wrote:
mpetach () opstools1:~>    telnet 25
Connected to static-host-219-90-94-56.tri.ph.
Escape character is '^]'.
ehlo yahoo.com
554 SMTP synchronization error
Connection closed by foreign host.
mpetach () opstools1:~>

I imagine when port 25 stops giving 5xx
failure message back, mail reception
might improve.   ^_^;

Works fine for me, your getting an error because your trying to send a
command before receiving the first 220, aka RFC violation.  As long as you
connect, wait a moment without trying to send a command, your fine.


See, that's what happens when you ask networking people
to try to troubleshoot mail issues.  ^_^;;

Sorry about that.  :(


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