Search two DNS Sources

[Rob Mallard]

I have two DNS servers, a private internal root server and a public server on the Internet. I want to first search the internal then if the host is not found search the external server. Is this possible?

Thanks!

[Brian M. Fisher]

If you are trying to point your HP box to an existing DNS server, create the file /etc/resolv.conf with two entries:
domain companydomain.com
nameserver ###.###.###.###

a second and third nameserver line is allowed.


Brian
<*(((>< er

[Tim Malnati]

The best way to handle this is to have your internal DNS server point to the external DNS server for resolution. Although this is more work for the internal server, requests will be cached there for the TTL period. In effect you will be drastically reducing the external requests made and therefor improve external bandwidth. You will also improve DNS response time on cached requests as well (more often than you would think).

[Albert E. Whale, CISSP]

Rob,

Certain versions of Bind require that you maintain a Pirmary Master DNS Server (one for your Domain) if it is going to be diconnected (a Private DNS).

You can establish the Private DNS (Internal Server) so that no one outside of your internal network can get to it, and then forward any unknown queries to the External DNS.

This will maintain your Private DNS internally, and Also allow you full DNS resolution Externally.

Please let me know if you need further assistance.

[Berlene Herren · Accepted solution]

Rob,
Yes. In your named.boot, place a line like this at the end

forwarders 15.253.24.10 15.253.24.10
<-- who do i punt to???

It is better to have them in there twice, to prevent timeouts. The IP address is the DNS IP on the External site.

Berlene

[Bill Hassell]

Note: the resolv.conf file allows up to 3 DNS servers. However, the alternate DNS servers are *NOT* contacted if the primary server does not locate a DNS entry. resolv.conf is strictly a fallback list. The second and third DNS servers will be queried if (and only if) the previous server is dead (not responding at all). That tis not the same as returning 'not found'. The primary (internal) DNS server should be configured to point to authoritative servers on the Internet if a non-local address is being requested.

[Michelle Barton]

Hi,
I am trying to get this going. Did you ever come to a resolution?

Thanks,
Michelle Hames
Xtra Corp