I have my mail forwarded in to Spamcop, then Spamcop set to forward it out again. It's been this way for quite some time, but this afternoon, something has gone wrong with the outgoing forwarding, so every non-spam email that should get forwarded out from Spamcop never makes it to the POP acocunt I check, and generates a bounceback like this:

From: Mail Delivery System <MAILER-DAEMON[at]c60.cesmail.net>
Date: 31 May 2007 20:40:36 -0400
Subject: Delivery Status Notification (Failure)
To: SRS0=Jq6k=LB=gmail.com=clongino[at]srs.perfora.net

The following message to <xxxx[at]c-lo.net> was undeliverable.
The reason for the problem:
5.1.0 - Unknown address error 550-"won't relay to xxxx[at]c-lo.net"

If I mail the xxxx[at]c-lo.net address directly from Gmail, the messages get through just fine. Any suggestions?

Not off the cuff, your receiving address is unavailable to cesmail.net for some reason (tracert from me shows no problem) ... Maybe there's a problem with one or more of the cesmail.net outgoing servers, in which case I would expect other users to be adding their voices.

I just sent test messages using SC webmail and also from my local PC using SC SMTP services and both made it out of the cesmail system just fine. I don't have a forwarding arrangement like Carlo's, however.

Carlo, there may be some blocking being done on the system that's supposed to receive the messages from cesmail.net...looks like 1and1.com hosting is involved.

DT

I'm having the same problem. I forward mail though my 1and1.com account to SpamCop for filtering and then forward back to 1and1.com. I've been doing this for years on multiple SpamCop accounts.

Beginning 5/31 the mail no longer goes through. And I get no notification of bounced mail. It just disappears.

So I've stopped routing to SpamCop until the problem is fixed. And as of this moment it's not.

Seems likely, but without the additional channel to receive the NDN that carlo has that is not certain. Anyway, enough to contact JT to see if further information is available, which I have done (well, I've sent an email, pointing "here"). 1and1 has had "issues" before, including SCBL listing of a "main mail handler" - http://forum.spamcop.net/forums/index.php?...ost&p=55296 - and internal problems - http://www.theregister.co.uk/2007/01/19/1and1_letters/ (2 pages) however there is nothing actually implicating the SC mail servers as a problem source AFAICS¹. Accordingly, may I suggest you and carlo either tackle 1and1 support or listen out within the internet generally for other indications of solutions that might be found within 1and1? DavidT seems to have nominated the problem, I think.

¹Well, I thought there maybe was at first. Not so sure now.

Sent a test e-mail via the Beta SMTP server to both accounts used to register here. May or may not prove anything, but .. it's a starting point. Not actually impressed with either address in use, but ..... assumedly they worked for the validation e-mail sequence to be able to post in here .....

Please resend test email to me. I just dumped my trash folder and was not looking for it.

Thanks,

peter[at]peterpeterpeter.com

Actually, that's kind of funny. I was doing other things, hitting the "Receive All" link off and on, wondering why nothing was showing up. To rule out the possibility that including your address in the BCC: line was an issue, I sent another test e-mail just to myself. Eventually, I hit the web interface to the Gmail account and yep, both of these test e-mails were found in the spam folder there .... I swear that the filters in use there are stumbling over the word 'spam' as seen within the SpamCop.net in the content (or possibly the From: line) ..... the actual e-mail shows as leaving the cesmal.net server, just as designed ..... what was sent;

What was received;

A bit hard to guess at what the "spammy" content must be, other than the obvious use of the 'spam' word .... that the body was just a couple of sentences with a URL could fit some 'construct' analysis/filter .. but as the body of my second test e-mail to just myself only included this as the body;

and it also ended up in the spam folder ..... I still back to the seeing and reacting to the 'word' spam being involved .... stupid or what?

Getting back on-topic .. will resend Peter's e-mail ... but have to ask .. is there any connection between the "non-receipt" situation and this "didn't look" scenario ????

No test mail received as of this am. Not in my Inbox and not in my Trash and not in my held mail on SpamCop.

And I now setup two test addresses.

test-sc[at]peterpeterpeter.com that is routed through SpamCop

and

test-no-sc[at]peterpeterpeter.com that is NOT routed through SpamCop

Using the first, the mail does not go through. Using the second it does.

Not what I was hoping for, but ..... due to the way I did those tests, I can give JT exact details on where to look in the log files.


Test e-mails headed to both of them ....

JT also notified with contents from the previous test ...... question at this point is "where is carlo?"

Neither e-mail received.

And FYI I really appreciate your help/interest in solving this problem. Also, FYI, I am not hurting now, other than getting a lot of spam, as I have cut SpamCop out of the loop until the problem is fixed ... wherever it is.

As far as I can tell, 1and1.com is having a serious problem with their DNS. This will cause problems for us, and other companies, in delivering email to them. I expect deliveries to be unreliable and intermittent.

Basically, this is what I see happening. It appears they are trying to change the IP addresses of their main incoming mail servers, but screwed it up. If you do some google searching, even in our own forums, you'll see that their main mail servers like mx00.1and1.com have been at 217.160.226.100 or around there.

Now, if you query one of their DNS servers directly, you'll see that they have moved to a totally different area:

jeff[at]delta2:~$ dig @ns28.1and1.com mx00.1and1.com


;; ANSWER SECTION:
mx00.1and1.com. 7200 IN A 74.208.5.3


Now, here's the problem. They apparently registered this same names directly with Network Solutions as if they are nameservers. So, when we ask the gtld servers about this name, we get this result:

jeff[at]delta2:~$ dig @c.gtld-servers.net mx00.1and1.com


;; ANSWER SECTION:
mx00.1and1.com. 172800 IN A 217.160.226.100

As you can see, that's a different IP address.

The problem is that this last IP doesn't actually respond to email any more. From the google search I mentioned above, it's obvious that at some point it did, but apparently it has been shut off.

I realize the whole thing is confusing, but basically it is valid for us to ask either the gtld server or 1and1's server for this IP address. And, depending on exactly the timing and the state of our caches, we may ask one or the other.

1and1.com really needs to fix their DNS. Once they do, mail will start being reliable again. Until then, we will keep queueing and retrying, but it won't be reliable.

JT

Here is the output of another tool I have. These are all servers which can be asked for the IP address of mx00.1and1.com. The fact that some servers return one answer and some a different answer is a serious problem.

1 mx00.1and1.com 192.12.94.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.26.92.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.31.80.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.33.14.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.35.51.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.41.162.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.42.93.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.43.172.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.48.79.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.5.6.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.52.178.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.54.112.30 172800 A 217.160.226.100
1 mx00.1and1.com 192.55.83.30 172800 A 217.160.226.100
1 mx00.1and1.com 74.208.2.3 7200 A 74.208.5.3
1 mx00.1and1.com 74.208.3.3 7200 A 74.208.5.3

Thanks Jeff and to Wazoo too.Peter and carlo, you have Jeff's data, above, to take to 1and1 (assuming that is also affecting c-lo.net, using 1and1 referrer/hosting), noting also (my emphasis)I also see possible conflicts at http://www.senderbase.org/senderbase_queri...ing=perfora.net

I sent this link and a copy of JT's analysis to 1&1. I'll keep you all posted.

Bear in mind, this is pretty esoteric stuff. The first 1 or 2 or even 5 replies you get from them will probably be wrong. If they check their DNS from internally, it will probably not show the same thing we see from the outside. And, they will tell you customers are receiving mail fine.

If you can get someone who actually understands DNS, the problem should be immediately apparent. But, I've just checked and it is still there so it's apparently going on for days without anyone there noticing.

I brought this up on a forum of email experts and the general consensus was that 1and1 has screwed this up. I don't have any backdoor way of contacting them to tell them, though.

JT

JT,

This is 1&1's response.

"I will escalate this information to our administrators in order for them to have a look into the server As you can see it in here it seems that the registered IP on the TLD nameserver is different from the A record being set on the 1and1 DNS."

They will now run with it. But if you have anything you want me to tell them in response to their email, I'd be happy to relay it to them.

Peter

Wow, I'm surprised. That looks like the guy basically understands the issue and is escalating it up to people who can fix it. Kudos to them, hopefully it will get fixed.

JT

No additional response back from 1&1 yet. But all of the test messages I sent since last Saturday and three test messages set by wazoo were all in mail box this am. So I sent another test message and it went through immediately. Thus I suspect that the problem is fixed. More when I hear from 1&1.

Not fixed in their DNS actually. But, it is an intermittent problem. Depending on the exact state of our cache at any given time, we might happen to pull from their DNS servers instead of the root DNS servers. When that happens, it will start working for a while. It could go away at any time, though, until they actually fix the problem.

JT

JT, it seems to be working now e.g. test messages I sent Thursday and today are delivered "instantly".

But I have not heard back from 1&1.

What I'd like to do is to ask 1&1 for a status on the fix but I'd prefer to tell them that the problem is not fixed, if that is the case, when I ask for the status.

So, from what you can see, is the problem fixed? And if not, do you have a "smoking gun" I can send them?

Thanks,

Peter

http://www.dnsstuff.com/tools/lookup.ch?%2....com%26type%3DA

How I am searching:
Searching for mx00.1and1.com A record at k.root-servers.net [193.0.14.129]: Got referral to l.gtld-servers.net. (zone: com.) [took 124 ms]
Searching for mx00.1and1.com A record at l.gtld-servers.net. [192.41.162.30]: Got referral to ns28.1and1.com. (zone: 1and1.com.) [took 39 ms]
Searching for mx00.1and1.com A record at ns28.1and1.com. [74.208.3.3]: Reports mx00.1and1.com. [took 13 ms]

Domain Type Class TTL
mx00.1and1.com. A IN 7200 74.208.5.3

http://www.dnsstuff.com/tools/traversal.ch....com&type=A
seems to suggest that things would appear to be OK at this point.

looking up "your" domain at http://www.mxtoolbox.com/index.aspx ;
ns28.1and1.com reports the following MX records:
Preference Host Name IP Address TTL
10 mxi00.1und1.com 212.227.15.169 86400
10 mxi01.1und1.com 212.227.15.150 86400

6/8/2007 2:46:11 PM Central Standard Time
DNS Host: Unknown
Email Host: Unknown

however, JT's remarks were about mx00.1and1.com, which I would have to assume came from hie looking at the log files on the outgoing server.

http://www.dnsstuff.com/tools/lookup.ch?%2....com%26type%3DA
How I am searching:
Searching for mx00.1and1.com A record at h.root-servers.net [128.63.2.53]: Got referral to b.gtld-servers.net. (zone: com.) [took 45 ms]
Searching for mx00.1and1.com A record at b.gtld-servers.net. [192.33.14.30]: Got referral to ns27.1and1.com. (zone: 1and1.com.) [took 188 ms]
Searching for mx00.1and1.com A record at ns27.1and1.com. [74.208.2.3]: Reports mx00.1and1.com. [took 13 ms]

Domain Type Class TTL Answer mx00.1and1.com. A IN 7200 74.208.5.3

http://www.dnsstuff.com/tools/traversal.ch....com&type=A
seems to suggest that the issues with mx00.1and1.com have been resolved ....

hwever, looking at "your" Domain's listing at http://www.dnsstuff.com/tools/lookup.ch?%2....com%26type%3DA ;

How I am searching:
Searching for mxi01.1und1.com A record at h.root-servers.net [128.63.2.53]: Got referral to d.gtld-servers.net. (zone: com.) [took 45 ms]
Searching for mxi01.1und1.com A record at d.gtld-servers.net. [192.31.80.30]: Got referral to nsa.schlund.de. (zone: 1und1.com.) [took 28 ms]
Searching for mxi01.1und1.com A record at nsa.schlund.de. [195.20.224.98]: Reports mxi01.1und1.com. [took 127 ms]

Domain Type Class TTL Answer
mxi01.1und1.com. A IN 86400 212.227.15.150
mxi01.1und1.com. A IN 86400 212.227.15.186
1und1.com. NS IN 86400 nsa.schlund.de.
1und1.com. NS IN 86400 nsa2.schlund.de.
nsa.schlund.de. A IN 86400 195.20.224.98
nsa2.schlund.de. A IN 86400 195.20.244.5

http://www.dnsstuff.com/tools/traversal.ch....com&type=A
Looking up at the 2 1und1.com. parent servers:

Server Response Time
nsa2.schlund.de [195.20.244.5] 212.227.15.150 212.227.15.186 124ms
nsa.schlund.de [195.20.224.98] 212.227.15.150 212.227.15.186 124ms
Status: Records all match.

Forwarding through SpamCop seems to be working fine for last few days.
----------------------
Trying for closure, I asked 1&1 tech support;

Please let me know the status of this problem.

1. Mail sent today through SpamCop is getting to me ASAP. That's good.

2. But, if you did not find and fix a problem, then maybe the problem is intermittent.

3. So, did you find and fix a problem? Yes? No?
----------------------
Their response today was;

Yes, this problem has been resolved by our mail administrators.
----------------------
I would have preferred more details. But, this and the fact that it's working will have to do.

Thanks for all your help. Without the detail you provided, my guess is the problem would still not be fixed.

Peter

Thanks for the update.... marking this resolved.