[SOLVED] Mail reception & admin console broken, no apparent reason !

[Bingo]

Hi all !

All of a sudden my server stopped accepting emails tonight !

I tried to connect to the admin console but it was throwing undecipherable content (firefox asked to open "octet-stream" content".

POP and IMAP work fine, as well as the webmail !

I tried to send an email to myself via an external account.
The smtp transaction worked fine (I checked via SMTP Check - Pingability.com because my ISP blocks pour 25, so I cannot test it from here), but the mail got bounced :

This is the Postfix program at host mydomain.com.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to <postmaster>

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

			The Postfix program

<me@mydomain.com>: mydomain.com



Reporting-MTA: dns; mydomain.com
X-Postfix-Queue-ID: BBCC01848811
X-Postfix-Sender: rfc822; me@othermail
Arrival-Date: Thu, 22 May 2008 21:50:28 +0200 (CEST)

Final-Recipient: rfc822; me@mydomain.com
Action: failed
Status: 5.0.0
Diagnostic-Code: X-Postfix; mydomain.com

Connecting via ssh worked, but a "zmcontrol status" showed everything was up and running !

I've restarded all services but it did not help. I've rebooted the server but it still doesn't work !

I don't know what to check next !

I am absolutely not an expert in linux, so I am quite lost...

I almost forgot the important part :
Zimbra 4.5.4
Fedora Core 4

Thanks for helping !

[phoenix]

You need to provide some information from the log files to see what errors are in there.

[Bingo]

Well, there are a lot of them !
I think I narrowed down the problem to a DNS issue.

My server is behind a Firewall with a private address.
I had a DNS server in this private network before, but not anymore.

When I try "host ldap.mydomain.com", it says :
ldap.mydomain.com is an alias for hostname.mydomain.com (correct)
hostname.mydomain.com has address EXTERNAL IP (not correct)

I have added an entry in /etc/hosts so that ldap.mydomain.com and hostname.mydomain.com point to the private address, but apparently this is ignored !

When I ping those addresses though, the private IP is used !

Do I really have to setup a split DNS configuration here, or is there a quick fix that could work ?
Thanks a lot !

[phoenix]

My server is behind a Firewall with a private address.
I had a DNS server in this private network before, but not anymore.

Why did you remove it?

Do I really have to setup a split DNS configuration here, or is there a quick fix that could work ?!

Yes, you need a split DNS set-up. Postfix needs to be able to resolve the LAN IP of the server, without DNS it can't do that.

[Bingo]

Why did you remove it?

This server has just been upgraded, the new one as no DNS server.

Yes, you need a split DNS set-up. Postfix needs to be able to resolve the LAN IP of the server, without DNS it can't do that.

OK, I thought I could find a quick and dirty workaround to force LDAP to use my hosts file instead of DNS lookup. Impossible then ?

[phoenix]

No, not possible I'm afraid. As I said, Postfix does a DNS lookup for the server and if it can't find it then mail gets deferred. Just set-up the split dns and you deferred mail will get delivered.

[Bingo]

OK thanks a lot phoenix !
Now, I am not very familiar with named, I hope I am not going to destroy everything ?

The wiki article mentions says, for named.conf :

zone "server.example.com" {
type master;
file "db.server.example.com";
};


Am I right to assume that server.example.com is my ZONE, not my server name ?


Then in my db.mydomain.com, the article only mentions MX, SOA and A records, but I believe I have to write a complete zone file ?

[phoenix]

Which operating system are you using? When I initially installed Zimbra I found that DNS In A Nutshell thread was the easiest to follow, the second post in that thread should tell you what you need to do.

[Bingo]

Which operating system are you using? When I initially installed Zimbra I found that DNS In A Nutshell thread was the easiest to follow, the second post in that thread should tell you what you need to do.

I am using FC4.

I think it works now, this article was indeed a bit more precise than the wiki !

Thanks a lot for your help, you saved my day !!!

[phoenix]

Glad you've fixed it.