DNS NT Server as Primary

[Verónica Muñoz Segovia]

I everybody!

My company have three sites named CMX1, CMX2 and CMX3, each one has a DNS NT Server, and the UNIX Servers for each plant has that NT DNS Server defined.

Today the NT Admin turn off the DNS forwards, and in that moment if anybody could conect to any of the servers by telnet we had a delay, about 20 seconds. I configure DNS on Name Server Switch from SAM I put the first source /etc/hosts and as sencond DNS.

If I put only /etc/hosts the conection by telnet is immediately. Why is this happening?

Or if the NT Admin turn on again the forwarders, my problem is resolve, I don't have any NT experience, and I don't know what those forwards do.

Then, these are my questions?

Why happend that with the turn on, turn off of the NT forwards?

Why I resolve my problem if is only configure the /etc/hosts in the Name Service Switch?

What others alternatives are possible to avoid this big problem to me? Could I put HP-UX as a secondary DNS?

I have never done a DNS Unix, somebody could help me?

I know there are a lot of questions but I will appreciated your comments.

Best Regards,

Veronica

[James R. Ferguson · Accepted solution]

Veronica:

1. The delay after the NT server was turned off was a timeout period during which DNS was attempting to get an answer from the nameserver.

2. Since you used /etc/hosts first (according to /etc/nsswitch.conf you saw no delay -- the name was resolved.

3. To see how this works, do:
# nslookup
> policy

4. Yes, it is advisable to have at least two nameservers. Configure them in /etc/resolv.conf in the order you see best.

5. For BIND/DNS documentation, see:
http://docs.hp.com/hpux/onlinedocs/B2355-90759/B2355-90759.html

...JRF...

[Craig A. Sharp]

Veronica,

Just some additional info for you.

DNS forwarders are used to define a set of additional name servers external to the physical DNS server. Sometimes they are called helpers.
If the DNS is unable to resolve the request, the server will forward the request to one or both of the forwarders for resolution.

Craig

[Verónica Muñoz Segovia]

James, I tried the nslookup and something strange happends on one of the servers, with policy it display:

#Lookups = 2
files [RCCR] dns [RRRR]
> casper

looking up FILES
Trying DNS
*** daffy.cmx1.cel.com can't find casper: Non-existent domain

My domain is mx-mty1.celestica.com, like this is defined in the /etc/resolv.conf
domain mx-mty1.celestica.com
nameserver 32.94.96.10 #daffy

Why is displying that different domain?