Need help with DNS please

jim.thornton · 08-12-2011, 06:17 PM

I'm hoping that someone here can help me out please. I've installed Ubuntu 10.04-LTS (lucid) onto a Guest VM under ESXi 4.1.

My goal is to setup this server as a mail server with Funambol for syncing my iPhone and then Enkive for archiving the mail. Basically, I'm trying to create server that will be able to provide the same functionality as Microsoft Exchange, BES or MobileMe. I want to do this for two reasons... 1) I'm in need of a solution that can be on my local server and not rely on a hosted solution. 2) There is a possibilty of having to scale this setup and a hosted solution will end up getting too costly.

So... Here is my dilemma: My cousin helped me setup a test environment last night, but he was suppose to "show me" how to setup the DNS but he just went and did it and then said he would show me after. Well, after, he started talking crazy jargon and I didn't understand it. Well, I've now created a snapshot to try a different solution and I'm trying to setup the DNS again and I can't get it working.

Question: What steps do I need to take to correctly configure DNS? Right now he suggests that I get the DNS working within my server/network environment before sending having the internet connected to it. However, I don't know how that can be tested.

Can anyone please give me a step by step on how to setup DNS correctly? I've installed webmin, so preferrably using webmin as the interface is a bit easier than command line. However, he was testing it with nslookup last night but I can't figure out how to do that.

frankbell · 08-12-2011, 07:15 PM

Assuming he used BIND (the most likely choice), the manuals are here:

http://www.bind9.net/manuals

jim.thornton · 08-12-2011, 08:23 PM

Thank you for the link. However, I would really rather a step by step. Trying to understand the BIND manual is very overwhelming.

jim.thornton · 08-12-2011, 09:03 PM

Maybe it might be better to ask specific questions. So, here is my first question.

Is my cousin correct when he says that I should get everything working with my MTA within my local domain before "opening" the door to the internet?

frankbell · 08-12-2011, 09:12 PM

Giggling "bind step-by-step" turns up a lot of links.

Here's one.

http://linux-sxs.org/internet_serving/dns.html

I don't know enough to comment on your cousin's caution.

jim.thornton · 08-12-2011, 11:33 PM

Okay... I've been reading up quite a bit. All the tutorials tell me what each record type is for, how to setup a master/slave zone, etc. What I need to know is what zones are required for this to work.

Here is what I have so far:

Linux hostname set to: myname.local

I've created a Master zone: myname.local

Here are my records:
myname.local. NS mail1.myname.local.
mail1.myname.local A 192.168.2.50
myname.local. MX 10 mail1.myname.local.

I've create a Master zone (reverse): 192.168.2

Here are my records:
2.168.192.in-addr.arpa. NS Default mail1.myname.local.
50.2.168.192.in-addr.arpa. PTR Default mail1.myname.local.

Webmin (or BIND) created the following master zones:
Root Zone
0
127
255
localhost

My problem is that I'm now trying to test things to make sure they are setup correctly. If I goto the command prompt and type "# dig localhost" I get the ANSWER field returned. If is type in "# dig myname.local" or "# dig mail1.myname.local" there is no ANSWER field returned. I have applied the settings with the BIND module.

Can someone please tell me what I've done wrong? Here is what I'm getting in response:
# dig localhost

Code:

 # dig localhost

; <<>> DiG 9.7.0-P1 <<>> localhost
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 48651
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;localhost.                     IN      A

;; ANSWER SECTION:
localhost.              1       IN      A       127.0.0.1

;; Query time: 1 msec
;; SERVER: 192.168.2.1#53(192.168.2.1)
;; WHEN: Sat Aug 13 00:30:33 2011
;; MSG SIZE  rcvd: 43

# dig thornton.local

Code:

# dig thornton.local

; <<>> DiG 9.7.0-P1 <<>> thornton.local
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 15237
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;thornton.local.                        IN      A

;; Query time: 1 msec
;; SERVER: 192.168.2.1#53(192.168.2.1)
;; WHEN: Sat Aug 13 00:31:34 2011
;; MSG SIZE  rcvd: 32

# dig mail1.thornton.local

Code:

# dig mail1.thornton.local

; <<>> DiG 9.7.0-P1 <<>> mail1.thornton.local
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 55887
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;mail1.thornton.local.          IN      A

;; Query time: 2 msec
;; SERVER: 192.168.2.1#53(192.168.2.1)
;; WHEN: Sat Aug 13 00:32:45 2011
;; MSG SIZE  rcvd: 38

I don't understand what I've done wrong, it all looks correct to me.

jim.thornton · 08-13-2011, 12:45 AM

Wow! I think I have it working now. I went into the DNS & Hostnames section of Webmin and noticed that it was pointing the DNS to my gateway 192.168.2.1 instead of my local machine. I changed it to 192.168.2.50 and now I am getting an ANSWER with dig.

dig myname.local was not giving an ANSWER section but # dig mail1.myname.local was. As a result, I went in and added another A record and it is now returning an ANSWER section. Is this correct? Have I named my hostname correct (myname.local) or does that need to change?

Finally, I can't see a PTR response from the dig tool which I though was automatically entered if you add a Master Zone (reverse)? Is this not correct?