[Samba] samba_dlz Failed to configure reverse zone

[Lars Hanke]

I just upgraded bind9 on my backup DC to 9.9.5-7-Debian and restarting 
the service failed:


Dec 22 12:25:55 verdandi named[18534]: starting BIND 9.9.5-7-Debian -u 
bind -4
Dec 22 12:25:55 verdandi named[18534]: built with '--prefix=/usr' 
'--mandir=/usr/share/man' '--infodir=/usr/share/info' 
'--sysconfdir=/etc/bind' '--localstatedir=/var' '--enable-threads' 
'--enable-largefile' '--with-libtool' '--enable-shared' 
'--enable-static' '--with-openssl=/usr' '--with-gssapi=/usr' 
'--with-gnu-ld' '--with-geoip=/usr' '--with-atf=no' '--enable-ipv6' 
'--enable-rrl' '--enable-filter-aaaa' 'CFLAGS=-fno-strict-aliasing 
-fno-delete-null-pointer-checks -DDIG_SIGCHASE -O2'
Dec 22 12:25:55 verdandi named[18534]: 
----------------------------------------------------
Dec 22 12:25:55 verdandi named[18534]: BIND 9 is maintained by Internet 
Systems Consortium,
Dec 22 12:25:55 verdandi named[18534]: Inc. (ISC), a non-profit 
501(c)(3) public-benefit
Dec 22 12:25:55 verdandi named[18534]: corporation.  Support and 
training for BIND 9 are
Dec 22 12:25:55 verdandi named[18534]: available at 
https://www.isc.org/support
Dec 22 12:25:55 verdandi named[18534]: 
----------------------------------------------------
Dec 22 12:25:55 verdandi named[18534]: adjusted limit on open files from 
4096 to 1048576
Dec 22 12:25:55 verdandi named[18534]: found 4 CPUs, using 4 worker threads
Dec 22 12:25:55 verdandi named[18534]: using 4 UDP listeners per interface
Dec 22 12:25:55 verdandi named[18534]: using up to 4096 sockets
Dec 22 12:25:55 verdandi named[18534]: loading configuration from 
'/etc/bind/named.conf'
Dec 22 12:25:55 verdandi named[18534]: reading built-in trusted keys 
from file '/etc/bind/bind.keys'
Dec 22 12:25:55 verdandi named[18534]: using default UDP/IPv4 port 
range: [1024, 65535]
Dec 22 12:25:55 verdandi named[18534]: using default UDP/IPv6 port 
range: [1024, 65535]
Dec 22 12:25:55 verdandi named[18534]: no IPv6 interfaces found
Dec 22 12:25:55 verdandi named[18534]: listening on IPv4 interface lo, 
127.0.0.1#53
Dec 22 12:25:55 verdandi named[18534]: listening on IPv4 interface eth0, 
172.16.10.17#53
Dec 22 12:25:55 verdandi named[18534]: generating session key for 
dynamic DNS
Dec 22 12:25:55 verdandi named[18534]: sizing zone task pool based on 22 
zones
Dec 22 12:25:55 verdandi named[18534]: Loading 'ad.microsult.de' using 
driver dlopen
Dec 22 12:25:56 verdandi named[18534]: samba_dlz: started for DN 
DC=ad,DC=microsult,DC=de
Dec 22 12:25:56 verdandi named[18534]: samba_dlz: starting configure
Dec 22 12:25:56 verdandi named[18534]: zone 10.16.172.in-addr.arpa/NONE: 
has 0 SOA records
Dec 22 12:25:56 verdandi named[18534]: zone 10.16.172.in-addr.arpa/NONE: 
has no NS records
Dec 22 12:25:56 verdandi named[18534]: samba_dlz: Failed to configure 
zone '10.16.172.in-addr.arpa.'
Dec 22 12:25:56 verdandi named[18534]: loading configuration: bad zone
Dec 22 12:25:56 verdandi named[18534]: exiting (due to fatal error)
Dec 22 12:25:56 verdandi named[18534]: samba_dlz: shutting down

It used to run before the update, but a zone with SOA and NS entries is 
of course something strange. The failing zone was fresh, when it first 
started. In fact as viewed from the DC it may only have contained - and 
still contain - the secondary DC itself.

Thanks for your help,
  - lars.