Overwrite Nameserver (STUB?)

Hi,

(IPs, hostnames and domains are fictional, but realistic.)

Description

my goal is to setup a local nameserver (knot, the machine is known as vanadium, IP 192.168.5.3) and a local kresd (on machine palstek, 192.168.5.2) to use this nameserver for any local-domains (example.org). So, for a request www.example.org, kresd should use vanadium as nameserver, instead of the public nameserver (a.iana-servers.net..., 199.43.135.53...). The differences to #349 is, nameserver instead of hints.

My first try was to use policy.STUB: policy.add( policy.suffix( policy.STUB( "192.168.5.2"), {todname('example.org.')}))

But vanadium is a non-recursive server, but STUB expects a recursive. So troja CNAME www.heise.de. on vanadium, will be unresolved; kresd will not follow this CNAME. A local CNAME lieschen CNAME mueller works fine.

We have problems with some clients, which expects an A-record, not a CNAME. I would expect, that a recursive DNS-Server should follow the CNAME and it does it, if it is a not the example.org.-zone.

Configs for STUB-example

Zone

$TTL 60
@ SOA vanadium.example.org root.example.org ( 2018121103 28800 14400 3600000 86400 )
  NS vanadium
  A 192.168.5.12
troja    CNAME www.heise.de.
mueller  A 192.168.5.24
lieschen CNAME mueller

kresd.conf

user( 'knot-resolver','knot-resolver')
cache.size = 1*GB
modules = { 'policy', 'stats', 'predict' }
verbose(true)
predict.config(20, 72)
policy.add( policy.all( policy.QTRACE))
policy.add( policy.suffix( policy.STUB( "10.91.53.3"), {
  todname('example.org.')
}))

Tests for STUB-example

Simple A-Record, no problems:

# dig mueller.example.org
;; ANSWER SECTION:
mueller.example.org.    60      IN      A       192.168.5.24

CNAME, the non-recursive-Server already followes the record:

# dig lieschen.example.org
;; ANSWER SECTION:
lieschen.example.org.   60      IN      CNAME   mueller.example.org.
mueller.example.org.    60      IN      A       192.168.5.24

The unfollowed CNAME-record:

# dig troja.example.org
troja.example.org.      60      IN      CNAME   www.heise.de.

I had expect as answer also the A-Record www.heise.de. 86400 IN A 193.99.144.85

So, STUB seems not to be the correct solution for my goal. Also the description of stub-dns is different to my goal.

• But how I can overwrite the Nameserver of my domain in kresd.conf?
• Or how it is possible to use STUB, but kresd tries to follow CNAMES, if A-record was not provided?

BR Denis