A better DNS Understanding

metallica1973 · 12-16-2006, 03:37 PM

I have setup BIND 9 as a CACHE server on a SUSE 10 box. I think that I have it setup right. My question is as such:

If my DNS box is setup right, then all I have to do is just edit the resolv.conf on the linux clients and add the DNS server ip address and on the windows boxes just add it to my TCPIP setting and BAM It should be able to ping all the host in my network or is there additional stuff that I need to add to my linux/windows boxes? I have read a little on the /etc/hosts file. Is that an additional file that I need to add hostname and ip address to it. If I have to di that then what good is my BIND server then.I guess I have to populate the zone files with the correct name to ip address statements. Please Clarify!

acid_kewpie · 12-16-2006, 04:20 PM

/etc/hosts is a file for local declarations of hostname and ip address mappings. it's only used for situations where the names are local to the box itself (e.g. localhost) or DNS is not available / suitable. if you can successfully complete a dig against the DNS server (dig google.com @12.34.56.78) then it should work fine when entered as a record in /etc/resolv.conf

chort · 12-16-2006, 11:45 PM

Caching-only nameservers are used so that you local machines can resolve names on the Internet without having to make potentially long queries across the Internet. The idea is the caching nameserver does that work for you and keeps the results so the next time a client asks for the answer, it can reply right away and save time.

What a caching-only nameserver does not do is give out answers about your local network names. You would need to perform a "normal" configuration of BIND with zone files and define each hosts' name and IP address in forward and reverse lookup zones.

metallica1973 · 12-16-2006, 11:49 PM

one more question:

I have created zone.Domain.Name with only one subnet (192.168.4.0) and my revp.192.168.4 reverse pointer file for only that subnet. If I have multiple subnets would I just add them to the zone.Domain.Name file and just create another revp.192.168.3.0 reverse pointer file for each subnet?

chort · 12-17-2006, 12:02 AM

Quote:

Originally Posted by metallica1973

one more question:

I have created zone.Domain.Name with only one subnet (192.168.4.0) and my revp.192.168.4 reverse pointer file for only that subnet. If I have multiple subnets would I just add them to the zone.Domain.Name file and just create another revp.192.168.3.0 reverse pointer file for each subnet?

That's correct.

metallica1973 · 12-17-2006, 12:17 AM

I restart NAMED (everything started up ok) and all of my client machines and when I try and ping from another workstation my DNS server by name or any other machine that I have specified in my zones it cannot translate anything by name. I have the ip address of the servers in the /etc/resolv.conf and in the windows TCPIP stack and still nothing. Any suggestions. In other words in doesnt work. Is there things that I should check?

metallica1973 · 12-17-2006, 12:39 AM

I restart NAMED (everything started up ok) and all of my client machines and when I try and ping from another workstation my DNS server by name or any other machine that I have specified in my zones it cannot translate anything by name. I have the ip address of the servers in the /etc/resolv.conf and in the windows TCPIP stack and still nothing. Any suggestions. In other words in doesnt work. Is there things that I should check?

chort · 12-17-2006, 12:46 AM

Try using dig to get more information. Suppose one of your machines is "box.domain.org", then do:

Code:

$ dig @127.0.0.1 box.domain.org.

This is assuming that you're logged into your DNS server. If you do this from another machine, substitute the IP address of your DNS server for 127.0.0.1. Also, post the contents of your named.conf file.

metallica1973 · 12-17-2006, 01:04 AM

here is my output:

PHP Code:


			
; <<>> DiG 9.3.2 <<>> @192.168.3.1 vicidious.calexica.com

; (1 server found)

;; global options:  printcmd

;; connection timed out; no servers could be reached

192.168.3.1 is my RADIUS server. I get that on all of my hosts.

metallica1973 · 12-17-2006, 01:07 AM

I get this when I ping from a client to the DNS server

PHP Code:


			
; <<>> DiG 9.3.2 <<>> @192.168.2.1 darcidious.calexica.com
; (1 server found)
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 3265
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;darcidious.calexica.com.    IN    A

;; Query time: 1 msec
;; SERVER: 192.168.2.1#53(192.168.2.1)
;; WHEN: Sun Dec 17 02:05:59 2006
;; MSG SIZE  rcvd: 41

Darcidious being my DNS server and when I just do a regular ping I get ping unknown host darcidious