SMTP Prob. and its not DNS (I think)... 1

[Bazagee]

Hi All,

Win2k box IIS5 SMTP Virutal server running (I wish)

I've read tested and tried the helpful hints for fixing our webservers smtp virtual server from this and other sites. It stopped working a day or so ago for (apparently) no reason. Yes, messages are going to the Queue and staying there. I've checked that the box can see a valid DNS server and that it can resolve MX records. I have checked that the binding order is correct on the NIC as per MS KB Q249104,(there was two but one is disabled and now not installed).

I'm getting Event ID 4000's &quot;Message delivery to the remote domain '<domainname>.com' failed.&quot; This box was once a member of a domain that we trashed, and joined it to the new domain, but its been working for months without problems. Did notice that in the SMTP virtual properties its FQDN showed the old domain. Changed that to new domain and checked with the &quot;check dns&quot; button. Ok. Other tidbit of info, we had recently changed our primary DNS box but used the old name and ip address of its replaced box (since the webserver is resolving then I don't think this is an issue). Other things I've tried; Start stopped IIS, rebooted the webserver, Start stopped the SMTP service, pulled out all the stuck mail from the Queue and put one known good message back into the pickup folder (it then settles in for an afternoon nap and a beer in the Queue folder again). I have also tried telneting to port 25 on the webserver and from the webserver to other SMTP servers. Have tried using Smarthost and not.

Haven't tried re-installing SMTP yet, its a production box so I'm trying to avoid reboots if possible, and the last reboot didn't work anyway. Sorry for the book review... any other suggestions... please And ok yeah, it's probably is a DNS issue - I just can't see it.

Thanks for any ideas.

 

[Killman]

In DNS suffix properties on the server, is it set to Change primary DNS suffix when Domain membership changes or is there something in the the DNS suffix of this computer?

 

[Bazagee]

Hi Killman,

No there is nothing in the DNS suffix. The &quot;Append primary and connection specific DNS suffixes&quot;, &quot;Register the connection's addresses in DNS&quot; and &quot;Use this connection's DNS suffix in DNS registration&quot; are the only items checked.

 

[Bazagee]

Sorry I didn't answer your question fully.
Yes the &quot;Change primary DNS suffix when domain membership changes&quot; checkbox is checked.

 

[Killman]

When you open ISM and look at SMTP vitual Server Properties--> General tab --> IP Address, what is it set to? All Unassigned? Are you suing the Default SMTP Virtual Server. If so have you tried adding the Server IP? You can also create a new SMTP site. Edit the default site changing the port under advance to another unused TCP port. Stop that site, create new SMTP site using all the same settings as before. If you need more details let me know, this worked for me in the past on a cluster.

 

[Bazagee]

Thanks for the reply Killman again,
I have tried all unassigned, website and machine specific IP addresses. No luck. I followed you instructions and made a test SMTP site using port 25. Tried changing a FQDN's, IP addresses and adding Smarthosts, but I get a nothing moving out of the Queue still. Is it Miller time yet?.....

I'll try removing SMTP from the server re-booting and re-installing it later tonight see if that works. %-)

 

[Killman]

Let me know how it goes. Dumb question, has anyone made changes to your firewall?

 

[Bazagee]

There is no such thing as a 'dumb question'. Just one you've heard a few times. No, I've checked it a couple of times now and with our firewall admin, there are no restictions on outgoing mail from any of the machines.

Thanks for the help. I'll post again after the re-install.
Cheers

 

[rbertram]

I had a very similar problem that started a couple weeks ago after installing a couple security patches from MS. I tried almost everything you have mentioned, but nothing fixed the problem. Everything was working great and then all mail would wet stuck in the queue.

A couple of days ago a installed the latest security patches from MS during a scheduled session, and after rebooting, all queued messages were delivered.

I don't know if the reboot fixed the problem the the new security updates. All I know is it just started working again.

 

[Bazagee]

SMTP Re-install made no difference. Drat. Bertram, I read your post on this forum when looking for clues, so I'm at the point that I think I have to try a service pack. I'll install Win2SP3 tomorrow and an IIS rollup and see what that brings. I'll report back then. Thanks

 

[Bazagee]

Firstly thanks for all the replys and help. After some late night testing on Friday it turns out that infact it is a Firewall issue. When the Firewall admin was away I punched a hole in our DMZ to see what would happen, and the mail started to flow. Today I get to beat on the Firewall admin!
Thanks again.