How to delegate subdomain? NS record ignored?

Hello

I'm using nsd 4.1.20 on OpenBSD 6.3. I'd like to delegate a subdomain,
but it just doesn't work… Below, I'll paste the configuration for the
domain "sheek.ch", where I'd like to delegate the subdomain "ghi"
(ie. ghi.sheek.ch) to ns1.exacttarget.com..

As you can see, I just added this line to the zone file:

ghi NS ns1.exacttarget.com.

But a "dig @9.9.9.9 -t ns ghi.sheek.ch" doesn't return anything; a
"dig @9.9.9.9 -t a abc.sheek.ch" (abc being defined in the same zone
file) returns what's defined there.

The zone is "live", ie. you can run the queries yourself.

It seems, as if nsd just doesn't send the NS record.

Would be great, if anyone could help.

Thanks a lot,
Alexander

fw2# cat /var/nsd/etc/nsd.conf
server:
        tcp-count: 100
        statistics: 3600
        verbosity: 2
        hide-version: yes
        identity: ns2.…
        interface: 185.…

remote-control:
        control-enable: yes

include: /var/nsd/etc/nsd-master.conf

fw2# cat /var/nsd/etc/nsd-master.conf
# …
# other zones before

zone:
        name: "sheek.ch"
        zonefile: "/var/nsd/zones/master/sheek.ch"
        outgoing-interface: 185.…
        provide-xfr: 172.18.0.0/16 NOKEY
        provide-xfr: 127.0.0.1 NOKEY
        notify: 46.… NOKEY
        provide-xfr: 46.… NOKEY

# other zones below
# …

fw2# cat /var/nsd/zones/master/sheek.ch
$ORIGIN sheek.ch.
$TTL 1d
@ IN SOA ns.…. sysadmin.…. (
        1565616181 ; serial
        1h ; refresh
        15m ; retry
        14d ; expire
        15m ) ; minimum

@ IN NS ns.zrh.…
@ IN NS ns.gva.…

@ 300 IN MX 1 aspmx.l.google.com.

www A 34.245.…
@ A 34.245.…

abc A 127.0.0.2

ghi NS ns1.exacttarget.com.

Hello

I'm using nsd 4.1.20 on OpenBSD 6.3. I'd like to delegate a subdomain,
but it just doesn't work… Below, I'll paste the configuration for the
domain "sheek.ch", where I'd like to delegate the subdomain "ghi"
(ie. ghi.sheek.ch) to ns1.exacttarget.com..

As you can see, I just added this line to the zone file:

ghi NS ns1.exacttarget.com.

But a "dig @9.9.9.9 -t ns ghi.sheek.ch" doesn't return anything; a
"dig @9.9.9.9 -t a abc.sheek.ch" (abc being defined in the same zone
file) returns what's defined there.

The zone is "live", ie. you can run the queries yourself.

It seems, as if nsd just doesn't send the NS record.

Would be great, if anyone could help.

For this to work ns1.exacttarget.com should serve NS/SOA records for
ghi.sheek.ch, but it doesn't.