Email delivery reject, host unknown

[Wilson_Lee]

Hi , I 'm having a problem when sending mail to certain domain only. Their mail server seems to reject my mail.

Here is the error:

host mail.x.x.x.x said: 554 5.7.1
<zimbra.xx.local>: Helo command rejected: Host not found (in reply to
RCPT TO command)

Do i need to change the hostname for the Zimbra server based on my actual domain?

my actual domain is yy.com and mx record is mail.yy.com

Now the setting in zimbra is zimbra.xx.local.

My Zimbra version is opensource and version5. It is setup behind a NAT router and with split DNS configuration. my DNS setting is based on zone xx.local.

[phoenix]

Now the setting in zimbra is zimbra.xx.local.

That's not a valid public domain name and is most likely what's causing your problem, you should have your valid domain name in there.

[Wilson_Lee]

Fyi, our DNS setting is hosted by external DNS server which maintain by vendor.

And zimbra server also I hv setup a internal DNS. Will I change the setting of DNS solve this issue?

Do I need to change the DNS setting (bind) as below to get rid the issue:

1) setup another zone which contains our mail server domain

2) update the host file and remove existing setting

how about zimbra? Do i need to do anything? cause during setup time, my domain is xx.local and the hostname for server is zimbra.xx.local

[phoenix]

You'll need to follow the instructions in the Split DNS article for configuring the DNS server and changing the hosts etc. files, you'll also need to change the server name - go to the wiki and search for the word "zmsetservername" (or you can also search the forums for that word).