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           };
           view "external" {
                   match-clients { key external; any; };
                   server 10.0.0.1 { keys external; };
                   recursion no;
                   ...
           };

Q: I have FreeBSD 4.x and "rndc-confgen -a" just sits there.

A: /dev/random is not configured. Use rndcontrol(8) to tell the kernel to use
   certain interrupts as a source of random events. You can make this permanent
   by setting rand_irqs in /etc/rc.conf.

   /etc/rc.conf
   rand_irqs="3 14 15"

   See also http://people.freebsd.org/~dougb/randomness.html

Q: Why is named listening on UDP port other than 53?

A: Named uses a system selected port to make queries of other nameservers. This
   behaviour can be overridden by using query-source to lock down the port and/
   or address. See also notify-source and transfer-source.

Q: I get error messages like "multiple RRs of singleton type" and "CNAME and
   other data" when transferring a zone. What does this mean?

A: These indicate a malformed master zone. You can identify the exact records
   involved by transferring the zone using dig then running named-checkzone on
   it.

   dig axfr example.com @master-server > tmp
   named-checkzone example.com tmp

   A CNAME record cannot exist with the same name as another record except for
   the DNSSEC records which prove its existance (NSEC).

   RFC 1034, Section 3.6.2: "If a CNAME RR is present at a node, no other data
   should be present; this ensures that the data for a canonical name and its
   aliases cannot be different. This rule also insures that a cached CNAME can
   be used without checking with an authoritative server for other RR types."

Q: I get error messages like "named.conf:99: unexpected end of input" where 99
   is the last line of named.conf.

A: Some text editors (notepad and wordpad) fail to put a line title indication
   (e.g. CR/LF) on the last line of a text file. This can be fixed by "adding"
   a blank line to the end of the file. Named expects to see EOF immediately
   after EOL and treats text files where this is not met as truncated.

Q: I get warning messages like "zone example.com/IN: refresh: failure trying
   master 1.2.3.4#53: timed out".

A: Check that you can make UDP queries from the slave to the master

   dig +norec example.com soa @1.2.3.4

   You could be generating queries faster than the slave can cope with. Lower
   the serial query rate.

   serial-query-rate 5; // default 20

Q: How do I share a dynamic zone between multiple views?

A: You choose one view to be master and the second a slave and transfer the
   zone between views.

   Master 10.0.1.1:
           key "external" {
                   algorithm hmac-md5;
                   secret "xxxxxxxx";
           };

           key "mykey" {
                   algorithm hmac-md5;
                   secret "yyyyyyyy";
           };

           view "internal" {
                   match-clients { !external; 10.0.1/24; };
                   server 10.0.1.1 {
                           /* Deliver notify messages to external view. */
                           keys { external; };
                   };
                   zone "example.com" {
                           type master;
                           file "internal/example.db";
                           allow-update { key mykey; };
                           notify-also { 10.0.1.1; };
                   };
           };

           view "external" {
                   match-clients { external; any; };
                   zone "example.com" {
                           type slave;
                           file "external/example.db";
                           masters { 10.0.1.1; };
                           transfer-source { 10.0.1.1; };
                           // allow-update-forwarding { any; };
                           // allow-notify { ... };
                   };
           };

Q: I get a error message like "zone wireless.ietf56.ietf.org/IN: loading master
   file primaries/wireless.ietf56.ietf.org: no owner".

A: This error is produced when a line in the master file contains leading white
   space (tab/space) but the is no current record owner name to inherit the
   name from. Usually this is the result of putting white space before a
   comment. Forgeting the "@" for the SOA record or indenting the master file.

Q: Why are my logs in GMT (UTC).

A: You are running chrooted (-t) and have not supplied local timzone
   information in the chroot area.

   FreeBSD: /etc/localtime
   Solaris: /etc/TIMEZONE and /usr/share/lib/zoneinfo
   OSF: /etc/zoneinfo/localtime

   See also tzset(3) and zic(8).

Q: I get the error message "named: capset failed: Operation not permitted" when
   starting named.

A: The capability module, part of "Linux Security Modules/LSM", has not been
   loaded into the kernel. See insmod(8).

Q: I get "rndc: connect failed: connection refused" when I try to run rndc.

A: This is usually a configuration error.

   First ensure that named is running and no errors are being reported at
   startup (/var/log/messages or equivalent). Running "named -g <usual
   arguments>" from a title can help at this point.

   Secondly ensure that named is configured to use rndc either by "rndc-confgen
   -a", rndc-confgen or manually. The Administrators Reference manual has
   details on how to do this.

   Old versions of rndc-confgen used localhost rather than 127.0.0.1 in /etc/
   rndc.conf for the default server. Update /etc/rndc.conf if necessary so that
   the default server listed in /etc/rndc.conf matches the addresses used in
   named.conf. "localhost" has two address (127.0.0.1 and ::1).

   If you use "rndc-confgen -a" and named is running with -t or -u ensure that
   /etc/rndc.conf has the correct ownership and that a copy is in the chroot
   area. You can do this by re-running "rndc-confgen -a" with appropriate -t
   and -u arguments.

Q: I don't get RRSIG's returned when I use "dig +dnssec".

A: You need to ensure DNSSEC is enabled (dnssec-enable yes;).

Q: I get "Error 1067" when starting named under Windows.

A: This is the service manager saying that named exited. You need to examine
   the Application log in the EventViewer to find out why.

   Common causes are that you failed to create "named.conf" (usually "C:\
   windows\dns\etc\named.conf") or failed to specify the directory in
   named.conf.

   options {
           Directory "C:\windows\dns\etc";
   };

Q: I get "transfer of 'example.net/IN' from 192.168.4.12#53: failed while
   receiving responses: permission denied" error messages.

A: These indicate a filesystem permission error preventing named creating /
   renaming the temporary file. These will usually also have other associated
   error messages like

   "dumping master file: sl/tmp-XXXX5il3sQ: open: permission denied"

   Named needs write permission on the directory containing the file. Named
   writes the new cache file to a temporary file then renames it to the name
   specified in named.conf to ensure that the contents are always complete.
   This is to prevent named loading a partial zone in the event of power
   failure or similar interrupting the write of the master file.

   Note file names are relative to the directory specified in options and any
   chroot directory ([<chroot dir>/][<options dir>]).

   If named is invoked as "named -t /chroot/DNS" with the following named.conf
   then "/chroot/DNS/var/named/sl" needs to be writable by the user named is
   running as.

   options {
           directory "/var/named";
   };

   zone "example.net" {
           type slave;
           file "sl/example.net";
           masters { 192.168.4.12; };
   };

Q: How do I intergrate BIND 9 and Solaris SMF

A: Sun has a blog entry describing how to do this.

   http://blogs.sun.com/roller/page/anay/Weblog?catname=%2FSolaris

Q: Can a NS record refer to a CNAME.

A: No. The rules for glue (copies of the *address* records in the parent zones)
   and additional section processing do not allow it to work.

   You would have to add both the CNAME and address records (A/AAAA) as glue to
   the parent zone and have CNAMEs be followed when doing additional section
   processing to make it work. No namesever implementation supports either of
   these requirements.

Q: What does "RFC 1918 response from Internet for 0.0.0.10.IN-ADDR.ARPA" mean?

A: If the IN-ADDR.ARPA name covered refers to a internal address space you are
   using then you have failed to follow RFC 1918 usage rules and are leaking
   queries to the Internet. You should establish your own zones for these
   addresses to prevent you quering the Internet's name servers for these
   addresses. Please see http://as112.net/ for details of the problems you are
   causing and the counter measures that have had to be deployed.

   If you are not using these private addresses then a client has queried for
   them. You can just ignore the messages, get the offending client to stop
   sending you these messages as they are most probably leaking them or setup
   your own zones empty zones to serve answers to these queries.

   zone "10.IN-ADDR.ARPA" {
           type master;
           file "empty";
   };

   zone "16.172.IN-ADDR.ARPA" {
           type master;
           file "empty";
   };

   ...

   zone "31.172.IN-ADDR.ARPA" {
           type master;
           file "empty";
   };

   zone "168.192.IN-ADDR.ARPA" {
           type master;
           file "empty";
   };

   empty:
   @ 10800 IN SOA <name-of-server>. <contact-email>. (
                  1 3600 1200 604800 10800 )
   @ 10800 IN NS <name-of-server>.

   Note

   Future versions of named are likely to do this automatically.