DNS issues with Zimbra desktop on Ubuntu

[zincmaster]

Zdesktop dev/support team:

I have installed Zimbra desktop on 2 Ubuntu systems, and can not get it to find host names using the DNS server assigned in resolv.conf

When adding a Yahoo account, for instance, I get zimbra.imap.mail.yahoo.com host not found. This name is pingable on the command prompt, and the ports are open. All DNS queries made by Desktop seem to fail, UNLESS the entry is in /etc/hosts. If the entry is there it works fine.

This is obviously irritating b/c we can't add a hosts file entry for every possible email server a user might add into Desktop.

Is there something in the config I am missing here? Again, I know for a fact the ports are open and DNS works, b/c it works with Thunderbird on the same machine, and it also works if I put the entry in /etc/hosts.

My installs on OS X and Windows do not have this issue.

Attached zdesktop.log file in zip file

Thanks for your assistance,
Ed

[zincmaster]

still having the same issue.... any ideas?

i must be missing something obvious here - can someone clue me in?

[zincmaster]

Googling "java DNS resolution ubuntu" finally resulted in:

- Installing lib32nss-mdns package resolved the issues on one box. However, i installed this package before installing Zimbra.

on another box still have the same problem, but it did not have the binary when installed.

Does zimbra use its own JRE or does it use the default on Ubuntu? on the working box I have openjdk6 as default

[jjzhuang]

linux build of desktop comes with its own jre. I'm not sure why you are having dns issues. have you tried flushing dns cache and restarting zdesktop server?

[ajc13]

While I have not tried the above hosts file 'fix', I am having what looks like the same issue. My workstation (Ubuntu 8.10 x86_64) has no issues reaching my local mail servers via mutt or Evolution.

Might this be an issue of handling cnames?

$ host mail.XXXXX.net
mail.XXXXX.net is an alias for mda1.XXXXX.net.
mda1.XXXXX.net has address aaa.bbb.ccc.ddd

[ajc13]

(third reply attempt)

I too am seeing this issue on Ubuntu 8.10

No DNS issues otherwise.

Is there a problem with those addresses which are a cname (as many mailservers seem to have).

[phoenix]

Originally Posted by ajc13

Is there a problem with those addresses which are a cname (as many mailservers seem to have).

Yes, it's invalid to have a CNAME pointing to a mail server as they should have an A record.

[ajc13]

Also having trouble with GMail.

IF it is the CNAME causing the trouble then someone better tell google et. all

Actually - if I understand the below presence of a CNAME does not mean the A record does not exist.

Have Confirmed that the '/etc/hosts' "fix" as above works for my office imap server.

PS - this 'issue' also appears to effect links followed in messages if the default internal browser is used.

[y@w]

I'm connected to a mailserver that uses a CNAME with Zdesktop on Ubuntu 8.10..

If I'm not mistaken, the issue with having a CNAME pointing to a mail server is with MX records.

[phoenix]

Originally Posted by y@w

I'm connected to a mailserver that uses a CNAME with Zdesktop on Ubuntu 8.10..

If I'm not mistaken, the issue with having a CNAME pointing to a mail server is with MX records.

The issue is with using a CNAME and incorrect set-up of DNS records.

Beware Using CNAME and MX at the Same Time
Why You Shouldn’t Mix CNAME and MX
How Best to Use a CNAME

While using a CNAME can work and it's use is rather ambiguous in the RFC, it's far better to avaoind it's use when pointing to a mail server.