I just can't seem to understand split-dns :(

[xkill911]

I've been running a Zimbra email server for years now but I want to move it inside our Sonicwall. I have read and researched the wiki's and forums for hours and even tried it on a test server and just can't seem to get a grasp on split-dns.

does anyone have a "split-dns guide for dummies"?

Zimbra 7.1.3 GA 64bit
Ubuntu 10.04 LTS 64bit
Sonicwall TZ-210

DNS is hosted at godaddy.com

thanks!

[phoenix]

Originally Posted by xkill911

does anyone have a "split-dns guide for dummies"?

It's a fairly straightforward process: Split DNS - Zimbra :: Wiki

Originally Posted by xkill911

DNS is hosted at godaddy.com

A Split DNS is used when you are behind a firewall and/or NAT router.

[xkill911]

Originally Posted by phoenix

It's a fairly straightforward process: Split DNS - Zimbra :: Wiki

A Split DNS is used when you are behind a firewall and/or NAT router.

wow! obviously I'm struggling with it or I would not have made this post.

[Labsy]

Probably it has been discussed and explained many tmes here, but hey, what the hack...

Split DNS is meant for the purpose, which Phoenix already mentioned - when you have Zimbra behind NAT (router). This means,. you have:
- public IP, which is actually IP of WAN adapter of your router
- local IP, for example, 192.168.62.10, which is LAN IP of your ZIMBRA server

So, when user from internet ask public DNS server, hey DNS, do you know where this particular Zimbra is located?... DNS will respond with your PUBLIC IP.
And user will happily be able to browse to your Zimbra server from internet...of course, your router will NAT translate port 80 and 443 and 25 for mail to your LAN IP of Zimbra server.

From the other hand, if ZIMBRA asks, hey, what's my IP, your local DNS, which is probably your router, will respond with your PRIVATE IP.
...or with your PUBLIC IP?

Now, here is the question for you:
Which LOCAL DNS answer is correct - should from inside your LAN Zimbra server be resolved to:
a.) LAN IP
b.) or to PUBLIC IP?

Since you did not read/understand Split DNS, you probably do not know, that answer (a) is correct.
Which means, that:
- from OUTSIDE Zimbra's A-record in DNs should point to PUBLIC IP
- from INSIDE your network, Zimbra's A-record should point to LOCAL IP of Zimbra server

This diversity is called "Split DNS", because DNS answer depends on which side of your router you are.

If you have some very good router, like Cisco, Vyatta, Mikrotik or like, you could also set separate DNS zone on your router...if not: follow suggested article and you should be fine.

[xkill911]

sorry I guess I should have clarified more

I understand the way it should work but what i don't understand is during following the step's of the wiki or various other forum or internet articles, something always goes different or wrong and I hit a road block.

this is a production server and unless what i'm see'ing on the screen matches the steps I stop

[xkill911]

Originally Posted by Labsy

If you have some very good router, like Cisco, Vyatta, Mikrotik or like, you could also set separate DNS zone on your router...if not: follow suggested article and you should be fine.

since you said that i'm wondering if my sonicwall TZ-210 will handle it for me. it has some pretty powerful ablilities

[xkill911]

I had been struggling I think because of Bind, i'll try dnsmasq it looks easier

thanks

[dik23]

I found DNSMasq easier to deal with. You install it on each machine behind the NAT that needs to be able to see itself, or for that matter other NATed machines.

This was a lot of help for me :

Simple way to set up Split DNS

Hope this helps. Once you get your head around it it's pretty simple.

[Labsy]

Originally Posted by xkill911

...something always goes different or wrong and I hit a road block...

It would be much easier if you would describe that "something"

Regarding SonicWall TZ series...I had a quick look at doc and I could not find any relevant instructions for creating split DNS or manual local DNS zone for LAN.
So I would follow Dik32 suggestion and link to simply setup "hosts" file. Just make sure that your Zimbra "hostname" and "host" name resolve locally to LAN IP, while from internet-side to public IP.

[phoenix]

Originally Posted by xkill911

wow! obviously I'm struggling with it or I would not have made this post.

Nothing is 'obvious' until you tell us what the problem is. You asked for a #how to' and you got one.

Originally Posted by xkill911

sorry I guess I should have clarified more

I understand the way it should work but what i don't understand is during following the step's of the wiki or various other forum or internet articles, something always goes different or wrong and I hit a road block.

this is a production server and unless what i'm see'ing on the screen matches the steps I stop

The problem is, you haven't actually clarified anything other than to say 'I don't get it'. If you actually know what it's supposed to fo and stop when it doesn't look the same on your screen you could actually try telling us what wrong with your configuration or try some of the diagnostic steps in the wiki article. You've given us no information about what the problem actually is, I'm not a mind reader and don't know what you don't know or don't understand until you tell me what the problem is.