Based on the fact that a reboot temporarily fixes the issue I would look at:
NIC firmware / driver Firewall packet sniffing after a reboot until failure -Jeff Steward On Mon, Aug 30, 2010 at 2:13 PM, Steve Szabo <steve...@gmail.com> wrote: > > Using Exchange 2007, fully patched as of last month's patches. > Server 2008 SP2, current as Exchange. > No Edge server, Exchange is a standalone. > Server is NOT a domain controller. > > We have been having a problem the last couple of weeks with our Exchange > 2007 server and sending mail. There are some domains where the mail will > not be sent. Other domains are just fine. I have done the RBL thing via > MXToolbox, and we are not listed on any of the lists they cover. Checked for > any solutions to possible grey listing, and come up with no answers there > other than that Exchange can handle it. Black hole routers seemed a > possibility, but if the server is restarted, all mail in the queues goes > out, which pretty much rules out an MTU problem. DNS problems were > suggested, but I do not think that is a problem as mail goes out after a > restart, the internal DNS is located on another server, The initial > connection with the SMTP servers receiving mail is successful, and pinging > here, there, everywhere by name returns an IP and usually returns a > successful result for the ping. > > Near as I can determine, this is the end of the failed transactions: > MAIL FROM:<st...@mydomain.com> SIZE=20007, > RCPT TO:<u...@verizon.net>, > 250 2.5.0 Address and options OK., > 421 4.4.2 Timeout while waiting for command., > QUIT, > > Using TELNET to send to the problem domains is a crap shoot. Sometimes it > works, other times it times out as above. > > Remember, this only happens with some domains, not all. I can send to AOL, > but not Verizon.net. I can send to Gmail, but not to the domain of one of > our customers. A restart of the server, not a restart of services, will > resolve the issue for a period of time, but not more than a few hours. This > is hard to tell, since we never know what domains we will have problems > with, though Verizon (who is also our Internet and phone provider, seems to > be a constant). > > -- > \\Steve// > > --- > You are currently subscribed to exchangelist as: jstew...@gmail.com. > To unsubscribe click here: > http://lyris.sunbelt-software.com/u?id=8250069.b0422841180fe43d5a0d77a8237dbd1b&n=T&l=exchangelist&o=9079617 > (It may be necessary to cut and paste the above URL if the line is broken) > or send a blank email to > leave-9079617-8250069.b0422841180fe43d5a0d77a8237db...@lyris.sunbelt-software.com > --- You are currently subscribed to exchangelist as: arch...@mail-archive.com. To unsubscribe click here: http://lyris.sunbelt-software.com/u?id=8142876.1678b53fdef861a9e8adf304b808c1e6&n=T&l=exchangelist&o=9079633 or send a blank email to leave-9079633-8142876.1678b53fdef861a9e8adf304b808c...@lyris.sunbelt-software.com
