SMTP Email delivery, possible to view the queue?

[#1]

Hi everyone
We run our own email server with MS Small Business Server 2003.
We have our PlusNet email settings set to have our email delivered by SMTP to our static IP.
We're a small business with 15 users and we've had our email set up this way for over 8 years now, and it's been working fine.
Still is working fine really, but over the last couple of days I've noticed some strange behaviour.
The person who originally set the server up wrote a Scheduled Task which runs every 10 mins.
This scheduled task runs a batch file with the following command:

@echo off
finger postmaster@autoturn.plus.net

When that runs, a command prompt box appears on the screen of the server with the following output:
http://www.highbeeches.plus.com/exchange_plusnetautoturn.png
This box used to appear and then disappear after 2-3 seconds, saying usually between 1 and 15 messages queued
But for the past couple of days it's been displayed permanently with 5630 messages queued!
I've never seen this before.
Is that correct?
Is there any way I can view the messages that are trying to be delivered to us? The queue at PlusNet or something?
I'm just wondering if there's a massive message that's blocking the SMTP delivery.
When I try sending test messages from an external gmail account, they arrive pretty much immediately.
All our mail seems to be arriving ok - we've been receiving the usual amount messages - so that didn't give me any clues as to the problem. Everything seems fine/usual with the amount of mail we've been receiving.
Anyone have any ideas/suggestions on this?
Is there a way to view the PlusNet SMTP queue to see if there's any problems with that?
If anyone wants to do a DNS check or poke around then the domain name in question is dealer-world.com
I've not restarted the server yet, that's a pretty drastic step. Usually takes about 30-40 minutes to come back up fully due to our substantial message store and ageing hardware.
(I was planning to migrate to Zimbra later this year before the MS buyout of Yahoo hit the fan. I'm not a big fan of Exchange / SBS)
The event viewer error logs don't point to anything unusual either.
Thanks, Ben

[#2]

If you've not got this sorted out yet, have you checked the servers logs? (if it's coming in, they should be in the POP logs).
Additionally, ensure the following does not apply;
http://support.microsoft.com/?kbid=835734

[#3]

I suspect there may be a problem with autoturn for your account. I suggest you raise a ticket about it and specifically asking them to check if there actually is a large queue sitting there.

[#4]

Well it's been like that for a couple of days but today I checked it and that message has now disappeared!
When that getmail.bat script runs now, it says 1-30 messages which seems completely fine again.
I didn't restart the server, our ADSL router or IPCop firewall.
It didn't seem like there was a massive backlog of messages coming into our mailboxes overnight either.
Just a regular 5-10 or so spam per hour and a few other ones.
Thanks for the help and suggestions, but it seems to be working properly again now. I'll keep monitoring it and see if there's any further developments/problems.
On a wider question... what is the purpose of that getmail.bat script I mentioned above?
Why do we have to run the command finger postmaster@autoturn.plus.net to trigger mail delivery?
How does that differ from just changing the MX records for the domain name?
Thanks, Ben

[#5]

Autoturn is there to receive mail addressed to you if for any reason your own mail servers are not available (server down, connection down etc). In your MX records you will find it is the last entry. The finger command to autoturn says "hey I'm up, have you got any mail for me?" - autoturn will then send any queued mail to your server. Running it every 10 minutes seems rather excessive!

[#6]

Ah right ok, so it's basically a backup MX?
I did not know 10 minutes was excessive, it was set up by our local IT company who setup our Exchange server
I'm looking to migrate us to Zimbra, depending on this M$ buyout of Yahoo of course
I will change the delay of that scheduled task to 40 minutes.
Ok another vaguely related question... this time outgoing mail.
I have a suspicion that our Exchange server actually routes all its mail through PlusNet.
Is there any way I can check this?
Also, is there any advantage to doing it this way?
Or is there any disadvantage to setting SBS 2003 Exchange to send directly?
Is it even possible to set SBS 2003 to send directly, as an SMTP server?
Thanks, Ben

[#7]

SBS and indeed, every other Server version of Windows, has a built in SMTP server ........ personally I tend to recommend using it.
In your case, it's the POP (incoming mail) side that needs sorted out, not the SMTP side (though I'd still recommend using the built in SMTP server and have it route everything directly, rather than indirectly via PlusNet).
Your techie seems to favour the overly complicated, rather than simple methodology.

[#8]

Yes it is a backup MX.
If your server does go down it is worth having the finger set up in a command file so that you can manually initiate an immediate collection of mail when it comes back up.
If you set up your server to send direct the IP of the mail server will show up as being in Plusnet's pool of IP's for "dynamic" connections. Many mail servers refuse to accept mail from such IPs (a PC what has been compromised could spew out spam in that manner). Relaying via relay.plus.net avoids this. You are configured correctly.

[#9]

Quote from: MysteryFCM

SBS and indeed, every other Server version of Windows, has a built in SMTP server ........ personally I tend to recommend using it. In your case, it's the POP (incoming mail) side that needs sorted out, not the SMTP side (though I'd still recommend using the built in SMTP server and have it route everything directly, rather than indirectly via PlusNet). Your techie seems to favour the overly complicated, rather than simple methodology.

If he is using autoturn he is using SMTP mail delivery - not POP.
Relaying is the recommended method. I used to look after a SBS system and made the mistake of configuring it to send directly - two particular companies we did business with bounced all our email until I changed it to use relay.plus.net.

[#10]

Interesting ..... I've never had a problem when configuring direct delivery.
The only time I can see this being a problem is;
1. The servers IP is blacklisted on one or more spam blacklists
2. The server is not configured to send it's FQDN (i.e. the server I currently run sends mysteryfcm.co.uk as the FQDN as thats my servers domain name)
As for SMTP/POP, if the MX is set to the servers IP, it should be getting delivered directly, rather than requiring pickup via autoturn.

[#11]

Try reading what I said above! Autoturn is configured as the lowest priority MX record and is there for when the user's mail server is not available. When the server comes back up autoturn can be fingered and the mail is received immediately. Without autoturn it is up to the sending server to retry - some may retry after 12 hours (that is fairly normal) - some badly configured servers may give up immediatlely after getting no response on all MX records.

[#12]

My bad ..... I misread what you wrote 

[#13]

Thanks for all the help guys. Still seems to be working alright now.
So is this autoturn thing a specific PlusNet configuration?
Or do other backup MX providers just store it in a POP3 box or something to get downloaded?
I want to move our domain name to a different web host, and my plan was to just point the MX of the domain to our server. And possibly also have a backup MX.
I've seen a few things on the web saying that often backup MX is not really worth while, as it should get queued by the sending server anyway.
I'm a bit concerned about this sending directly thing though. I thought that was the point in running your own mail server?
So it is advisable to go through a relay?

[#14]

The problem with sending is that you have no control over the policies of the target server. They may choose reject emails because you are in the dynamic pool (all Plusnet users appear as such). Using relay.plus.net gets round that problem. That was my experience.

[#15]

So could you 'buy' a static IP and use that for sending out?
Even though it just redirects to my PlusNet static IP?