bind delegation

Question

I have nameservers and I wanted to delegate subdomains on nameserver A to nameserver X where X is a local workstation name server

example would be: TLD is company.com any queries to host.XXXX.company.com would be delegated to that XXXX's nameserver. X can vary as it would be some sort of 'personal' nameserver.

so i imagine company.com zone file would be like

$ORIGIN company.com. $TTL 6h

@ IN SOA company.com. root.company.com. (
  1
  1h
  30m
  7d
  1h)

  NS  ns.company.com.
  A   10.1.1.1

;so these names are potential XXXX
foo    A   10.1.1.3
bear   A   10.1.1.2
ns     A   10.1.1.1

---

and XXXX's(or lets say foo.company.com) zone file would be like (this is found in another nameserver, not the same as above)

$ORIGIN foo.company.com. $TTL 6h

@ IN SOA foo.company.com. root.company.com. (
  1
  1h
  30m
  7d
  1h)

  NS  ns.foo.company.com.
  A   10.1.1.3

ns     A   10.1.1.3

---

am i doing this right?

summary is, when someone would access foo.company.com, company.com NS would resolve it

but when lets say i have a host on foo, named 'test' so when someone accesses test.foo.company.com, it goes first to company.com but delegates it to foo.company.com name server and would resolve 'test' there.

Answer 1

I have no experience on sending a subzone of a zone to another dns server but in theory your logic is right:

Entry on /etc/named.conf for domain.com:

zone "domain.com" {
    type master;
    file "/var/name/domain.com.zone";
};

domain.com zone file /var/name/domain.com.zone:

; zone fragment for domain.com
; name servers in the same zone
$TTL 2d ; default TTL is 2 days
$ORIGIN domain.com.
@              IN      SOA   ns1.domain.com. hostmaster.domain.com. (
               2010101801 ; serial number
               2h         ; refresh =  2 hours 
               15M        ; update retry = 15 minutes
               3W12h      ; expiry = 3 weeks + 12 hours
               2h20M )    ; minimum = 2 hours + 20 minutes

; main domain name servers
              IN      NS     ns1.domain.com.
              IN      NS     ns2.domain.com.

; main domain mail servers
              IN      MX     10 mail.domain.com.

; A records for name servers above 
ns1           IN      A      10.0.0.1
ns2           IN      A      10.0.0.2

; A record for mail server above 
mail          IN      A      10.0.0.3

; Subdomain of domain.com
foo           IN      A      10.0.0.100

Entry on 10.0.0.100 dns server /etc/named.conf for foo.domain.com on the other dns server:

zone "foo.domain.com" {
    type master;
    file "/var/name/foo.domain.com.zone";
};

foo.domain.com zone file /var/name/foo.domain.com.zone on 10.0.0.100:

; zone fragment for domain.com
; name servers in the same zone
$TTL 2d ; default TTL is 2 days
$ORIGIN foo.domain.com.
@              IN      SOA   ns1.foo.domain.com. hostmaster.foo.domain.com. (
               2010101811 ; serial number
               2h         ; refresh =  2 hours 
               15M        ; update retry = 15 minutes
               3W12h      ; expiry = 3 weeks + 12 hours
               2h20M )    ; minimum = 2 hours + 20 minutes

; main domain name servers
              IN      NS     ns1.foo.domain.com.

; main domain mail servers
              IN      MX     10 mail.foo.domain.com.

; A records for name servers above 
ns1           IN      A      10.0.0.100

; A record for mail server above 
mail          IN      A      10.0.0.3

---

So from what i see it would send foo.domain.com to it is given ip at DNS A where it would be recognized as a domain on DNS B and would resolve whatever new entries it has.