Bind 8.4.4

Kevin Darcy kcd at daimlerchrysler.com
Thu Oct 21 21:16:03 UTC 2004


Marcos Rene wrote:

>Hello.
>
>I=B4m working with bind 8.4.4 to resolve my internal network when my=20
>DNS(ISP) does fail, how can i guarantee that my DNS internal does=20
>resolve machines local,
>if the hosts file of my DNS have other domain name, that doesn=B4t be th=
e=20
>name domain given for my ISP?
>
I'm not sure I understand the question. If you're using your ISP for=20
forwarding, then certainly you are dependent on them, to some extent,=20
for resolution of external names. If you can't reach their nameservers,=20
therefore there will be some sort of performance impact. Your options=20
are a) don't forward to your ISP's nameservers at all (usually the best=20
option), or b) use "forward first" mode instead of "forward only", so=20
that your nameservers will go out to the Internet themselves if the=20
forwarders are not available.

DNS doesn't use hosts files.

If the problem is that the domain that you use for *internal* hosts is=20
hosted on your ISP's nameservers, thus causing you to be unable to=20
resolve those names when your ISP's nameservers are unavailable, then=20
again you have two options: a) make your nameservers slaves of that=20
zone, or b) maintain a separate version of the zone on your nameservers.=20
Often (b) is implemented for security reasons anyway (because it's=20
usually a good idea to hide internal names from the Internet).

>and other cuestion:
>if my DNS local fails, is necessary upgrade it domain name in the DNS of=
=20
>my ISP? to resolve with it?
>

(My DNS local have a domain name different to domain give it for my DNS=20
of my ISP, is necessary an alias on the ISP DNS?
 =20

What I think you're asking is if you need to update the "domain" setting=20
in /etc/resolv.conf if your local DNS server is unavailable and you're=20
failing over to using your ISP for resolving names in your own domain.=20
This should not be necessary, since the "domain" parameter in=20
/etc/resolv.conf only instructs the local resolver how to qualify names.=20
So as long as your ISP's nameserver can resolve names in your domain,=20
your lookups should still work. Perhaps you were thinking that the=20
nameserver uses this parameter to qualify names (?) It's all done in the=20
local resolver, before the query is even sent to the nameserver.

>What meaning the file .CPR in the /usr directory as apparently my DNS=20
>does fail and its generate this file?
>
I've never heard of a /usr/.CPR file before. Are you sure this is being=20
generated by "named"?

                                                                        =20
                                                - Kevin





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