Table of Contents


1 Introduction

BIND, the most frequently used DNS server, normally keeps its zone data in zone files. This approach becomes inconvenient when the number of zones grows beyond a certain limit. When this happens, the obvious solution is to move all data to a database and make named read it from there. Recent versions of BIND include dynamically loadable zones (DLZ) feature1, which makes it possible to use such databases directly. However, DLZ has problems of its own, one of them being that it is unable to propagate glue records2.

The nssync utility provides an alternative solution, which makes it possible to keep your zone data in an SQL3 database without using DLZ and with glue records working.

It does so by periodically polling the database to determine which data have changed recently and converting the database into BIND zone files.

This edition of the nssync manual, last updated 1 December 2014, documents nssync Version 1.1.91. It is available in various formats. See This Manual in Other Formats, to select another format.

2 Overview

The nssync utility is normally started periodically from crontab. Upon startup it reads its configuration file, which supplies the necessary program settings. Then, if the settings require so, it verifies that no other copy of the nssync is already running. Further on, it parses the named configuration file named.conf to determine several settings needed for its further operation, in particular, the value of the ‘directory’ statement in the ‘options’ block.

Once these preliminary operations are over, nssync starts its main task. Its configuration file defines, among other data, one or more synchronization blocks. Each such block defines SQL statements which return information about DNS zones as well as the location of named configuration file where the zone statements for these zones are to be stored (it is supposed that this file is included somewhere in the main named.conf file). For each synchronization block, the utility retrieves the zone data from the database and formats them into separate zone files. Each of these files is then compared to an already existing one (locations of the zone files are defined in the synchronization block they pertain to). If the files differ, new zone file replaces the old one and a flag is set indicating that the named daemon needs to be restarted in order to read new configuration.

When this stage is finished, nssync reloads the name server (if required) and exits.

Several command line options can be supplied in order to modify the program’s behavior. In particular, it is possible to check the configuration file syntax or even instruct the utility to do everything, except modifying the zone files (a so-called dry-run mode). This allows you to debug your configuration before actually starting using nssync.

3 Configuration File

Nssync reads its settings from a configuration file nssync.conf located normally in the system configuration directory (usually /etc or /usr/local/etc, depending on compile-time options).

This chapter describes the syntax of that file in general. The chapter that follows describes the nssync-specific settings in detail.

The configuration file consists of statements and comments.

There are three classes of lexical tokens: keywords, values, and separators. Blanks, tabs, newlines and comments, collectively called white space are ignored except as they serve to separate tokens. Some white space is required to separate otherwise adjacent keywords and values.


Comments may appear anywhere where white space may appear in the configuration file. There are two kinds of comments: single-line and multi-line comments. Single-line comments start with ‘#’ or ‘//’ and continue to the end of the line:

# This is a comment
// This too is a comment

Multi-line or C-style comments start with the two characters ‘/*’ (slash, star) and continue until the first occurrence of ‘*/’ (star, slash).

Multi-line comments cannot be nested. However, single-line comments may well appear within multi-line ones.

3.2 Pragmatic Comments

Pragmatic comments are similar to usual single-line comments, except that they cause some changes in the way the configuration is parsed. Pragmatic comments begin with a ‘#’ sign and end with the next physical newline character.

#include <file>
#include file

Include the contents of the file file. If file is an absolute file name, both forms are equivalent. Otherwise, the form with angle brackets searches for the file in the include search path, while the second one looks for it in the current working directory first, and, if not found there, in the include search path.

The default include search path is:

  1. prefix/share/nssync/1.1.91/include
  2. prefix/share/nssync/include

where prefix is the installation prefix.

#include_once <file>
#include_once file

Same as #include, except that, if the file has already been included, it will not be included again.

#line num
#line num "file"

This line causes the parser to believe, for purposes of error diagnostics, that the line number of the next source line is given by num and the current input file is named by file. If the latter is absent, the remembered file name does not change.

# num "file"

This is a special form of #line statement, understood for compatibility with the C preprocessor.

In fact, these statements provide a rudimentary preprocessing features. For more sophisticated ways to modify configuration before parsing, see Preprocessor.

3.3 Statements

A simple statement consists of a keyword and value separated by any amount of whitespace. Simple statement is terminated with a semicolon (‘;’).

The following is a simple statement:

standalone yes;
pidfile /var/run/slb.pid;

A keyword begins with a letter and may contain letters, decimal digits, underscores (‘_’) and dashes (‘-’). Examples of keywords are: ‘expression’, ‘output-file’.

A value can be one of the following:


A number is a sequence of decimal digits.


A boolean value is one of the following: ‘yes’, ‘true’, ‘t’ or ‘1’, meaning true, and ‘no’, ‘false’, ‘nil’, ‘0’ meaning false.

unquoted string

An unquoted string may contain letters, digits, and any of the following characters: ‘_’, ‘-’, ‘.’, ‘/’, ‘@’, ‘*’, ‘:’.

quoted string

A quoted string is any sequence of characters enclosed in double-quotes (‘"’). A backslash appearing within a quoted string introduces an escape sequence, which is replaced with a single character according to the following rules:

SequenceReplaced with
\aAudible bell character (ASCII 7)
\bBackspace character (ASCII 8)
\fForm-feed character (ASCII 12)
\nNewline character (ASCII 10)
\rCarriage return character (ASCII 13)
\tHorizontal tabulation character (ASCII 9)
\vVertical tabulation character (ASCII 11)
\\A single backslash (‘\’)
\"A double-quote.

Table 3.1: Backslash escapes

In addition, the sequence ‘\newline’ is removed from the string. This allows to split long strings over several physical lines, e.g.:

"a long string may be\
 split over several lines"

If the character following a backslash is not one of those specified above, the backslash is ignored and a warning is issued.

Two or more adjacent quoted strings are concatenated, which gives another way to split long strings over several lines to improve readability. The following fragment produces the same result as the example above:

"a long string may be"
" split over several lines"

A here-document is a special construct that allows to introduce strings of text containing embedded newlines.

The <<word construct instructs the parser to read all the following lines up to the line containing only word, with possible trailing blanks. Any lines thus read are concatenated together into a single string. For example:

A multiline

The body of a here-document is interpreted the same way as a double-quoted string, unless word is preceded by a backslash (e.g. ‘<<\EOT’) or enclosed in double-quotes, in which case the text is read as is, without interpretation of escape sequences.

If word is prefixed with - (a dash), then all leading tab characters are stripped from input lines and the line containing word. Furthermore, if - is followed by a single space, all leading whitespace is stripped from them. This allows to indent here-documents in a natural fashion. For example:

<<- TEXT
    The leading whitespace will be
    ignored when reading these lines.

It is important that the terminating delimiter be the only token on its line. The only exception to this rule is allowed if a here-document appears as the last element of a statement. In this case a semicolon can be placed on the same line with its terminating delimiter, as in:

help-text <<-EOT
        A sample help text.

A list is a comma-separated list of values. Lists are enclosed in parentheses. The following example shows a statement whose value is a list of strings:

alias (test,null);

In any case where a list is appropriate, a single value is allowed without being a member of a list: it is equivalent to a list with a single member. This means that, e.g.

alias test;

is equivalent to

alias (test);

A block statement introduces a logical group of statements. It consists of a keyword, followed by an optional value, and a sequence of statements enclosed in curly braces, as shown in the example below:

server srv1 {
  community "foo";

The closing curly brace may be followed by a semicolon, although this is not required.

3.4 Preprocessor

Before actual parsing, the configuration file is preprocessed. The built-in preprocessor handles only file inclusion and #line statements (see Pragmatic Comments), while the rest of traditional preprocessing facilities, such as macro expansion, is supported via m4, which serves as external preprocessor.

The detailed description of m4 facilities lies far beyond the scope of this document. You will find a complete user manual in http://www.gnu.org/software/m4/manual. For the rest of this subsection we assume the reader is sufficiently acquainted with m4 macro processor.

The external preprocessor is invoked with -s flag, which instructs it to include line synchronization information in its output. This information is then used by the parser to display meaningful diagnostic.

An initial set of macro definitions is supplied by the pp-setup file, located in prefix/share/nssync/1.1.91/include directory.

The default pp-setup file renames all m4 built-in macro names so they all start with the prefix ‘m4_’. This is similar to GNU m4 --prefix-builtin option, but has an advantage that it works with non-GNU m4 implementations as well.

4 Nssync Configuration

4.1 General Settings

These settings modify the behavior of nssync as a whole.

Configuration: pidfile file

At startup, check if file already exists and is owned by an existing process. Exit if so. Use this statement to avoid accidentally running two copies of nssync simultaneously.

Configuration: tempdir dir

Sets the name for the temporary directory. This is a directory where nssync creates temporary zone files. The argument must point to an existing directory.

Configuration: check-ns bool

If set to true, nssync will check the list of NS servers prior to creating a zone file. The file will be created only if IPv4 address of one of the servers matches one of the IP addresses of the host on which nssync is run.

Configuration: named-conf file

Defines the full pathname of the named configuration file. Default is /etc/named.conf.

Configuration: bind-include-path list

Sets include search path for include directives found in BIND configuration. The argument is either a single directory or a list of directories (see list).

Configuration: zonefile-pattern pat

Defines the pattern for zone file names. The name of each zone file is created by expanding variable references in the pat argument. The following variable references are defined:


Name of the zone, without the trailing dot.


Zone synchronization tag (see Synchronization Block).

Both notations (with and without braces) are equivalent. The notation with curly braces should be used if the reference is immediately followed by a letter.

The default zone file pattern is ‘$zone.$synctag’.

Configuration: zone-conf pat

Defines the pattern for zone configuration file, i.e. a file containing zone statements.

The handling of pat is similar to that in zonefile-pattern, except that only the ‘$synctag’ reference is defined.

Configuration: compare-command cmd

Defines a command to be used for comparing two zone files. The cmd must be a command taking two files as its arguments and returning 0 if they are the same or non-zero if they differ. Nssync uses this command to determine whether a particular zone has changed. The following variable references are expanded in cmd:


Old zone file.


New zone file.

The default compare-command value is:

cmp $oldfile $newfile > /dev/null
Configuration: reload-command cmd

Defines a command to reload the nameserver. The default is ‘/usr/sbin/rndc reload’.

4.2 SQL Access

The following statements define the database server and the database to use:

Configuration: host hostname[:port-or-socket]

Defines the SQL server IP and port. The hostname can be either the server IP address or its hostname. The port-or-socket part, if supplied, can be either the number of TCP port to use instead of the default 3306 or the full pathname of the UNIX socket. In the latter case hostname is effectively ignored.

Configuration: database name

Sets the database name.

Configuration: ssl-ca file

Defines the name of the Certificate Authority (CA) file.

There are two ways to supply database access credentials. The simplest one is by using user and password statements:

Configuration: user name

Sets SQL user name.

Configuration: password arg

Sets SQL user password.

The drawback of this approach is that the password appears in plaintext, which means the permissions of the nssync.conf file must be tightened so as to avoid its compromise.

The following two statements provide an alternative, more safe and flexible way of setting access credentials:

Configuration: sql-config-file file

Read MySQL configuration from the option file file. See option files, for a description of MySQL option file format.

Configuration: sql-config-group name

Read the named group from the SQL configuration file.

To illustrate their use, suppose your nssync.conf file contains the following:

sql-config-file /etc/nssync.my;
sql-config-group nssync;

The the /etc/nssync.my will contain the actual SQL access configuration, which can look as in the example below:

socket = /var/db/mysql.sock
database = dns 
user = root
pass = guessme
Configuration: slave-status-file file

Use this statement if nssync reads data from a slave database. It allows you to avoid recreating zone files if the database information has not changed since the previous run.

If this statement is present, nssync will save the state of the SQL slave in file. Upon startup, it will read these data and compare them with the current state. If they are the same, it will exit immediately.

4.3 Synchronization Block

A synchronization block defines a set of zones to be synchronized from the database and configures SQL statements which return the zone data. This set is identified by synchronization tag, supplied as the argument to the sync statement:

# Define a synchronization block.
sync tag {
  # zone configuration file
  zone-conf pat;
  # pattern for new zone file names
  zonefile-pattern pat;
  # add these statements to each generated zone file
  add-statements text;
  # a query for retrieving SOA records
  soa-query string;
  # a query for retrieving NS and similar records
  ns-query string;
  # a query for retrieving the rest of RRs
  rr-query string;
  # a query for retrieving RRs from reverse delegation zones
  rev-rr-query string;

Statements within the sync block configure the zones:

Configuration: zone-conf pat

Defines the pattern for the name of zone configuration file for zones in this synchronization block. If not supplied, the global zone-conf statement will be used instead (see zone-conf).

Configuration: zonefile-pattern pat

Defines the pattern for zone file names. If not supplied, the global zonefile-pattern statement will be used instead (see zonefile-pattern).

Configuration: add-statements text

Append text to each generated zone statement. For example, the following can be used to redefine forwarders and query ACLs for zones in this synchronization block:

add-statements <<EOT
  forwarders { /* empty */ };
  allow-query { local-query-only; };

Notice the use of the here-document construct.

The following statements define which zones pertain to this particular synchronization block:

Configuration: soa-query string

A query for retrieving SOA records.

Configuration: ns-query string

A query for retrieving NS and similar records. Use the ‘$zone’ reference for the zone name.

Configuration: rr-query string

A query for retrieving the rest of RRs. Use the ‘$zone’ reference for the zone name.

Configuration: rev-rr-query string

A query for retrieving RRs from reverse delegation zones. Use the ‘$zone’ reference for the zone name.

Here is an example of a working sync directive:

sync external {
  zone-conf "/var/namedb/nssync/zones.external";
  zonefile-pattern "/var/namedb/external/db.${zone}";
  soa-query    "select zone, ttl, type, data, resp_person, "
               "serial, refresh, retry, expire, minimum "
               "from dns_soa where type='SOA' "
               "and view='external' order by zone";
  ns-query     "select ttl, type, data "
               "from dns_soa where zone='$zone' "
               "and type<>'SOA' and view='external'";
  rr-query     "select host, ttl, type, mx_priority, "
               "case when type='TXT' then "
               "concat('\"', data, '\"') "
               "else data end "
               "from dns_records "
               "where zone='$zone' and view='external' "
               "order by 1";
  rev-rr-query "select host, ttl, type, mx_priority, "
               "case when type='TXT' then "
               "concat('\"', data, '\"') "
               "else data end "
               "from dns_records "
               "where zone='$zone' and view='external' "
               "order by cast(host as unsigned)";

5 Invocation

The nssync is normally invoked periodically from a crontab, e.g.:

*/5 * * * *  /usr/sbin/nssync | /usr/bin/logger -t nssync -p local1.err

The following table summarizes available command line options:


Preprocess configuration file and exit.

-c file

Use file instead of the default configuration file.


Proceed even if slave status has not changed (see slave-status-file).


Do nothing, print almost everything; implies --debug --stderr. Use additional --debug options to get even more info.


Parse configuration file and exit. The return status is 0 if the syntax is OK, and 78 if errors were detected (see Exit Codes).

-D symbol=value

Define a preprocessor symbol.

-I dir

Add include directory.


Disable preprocessing.


Use command instead of the default preprocessor.


Increase debug level.


Debug configuration file lexer.


Debug configuration file parser.


Show configuration file summary


Print program version.


Give this help list.


Give a short usage message.

6 Exit Codes

Apart from issuing a descriptive error message, nssync attempts to indicate the reason of its termination by its error code. As usual, a zero exit code indicates normal termination. The table below summarizes all possible error codes. For each error code, it indicates its decimal value and its symbolic name from include/sysexits.h (if available).


Program terminated correctly.


The program was invoked incorrectly, e.g. an invalid option was given, or an erroneous argument was supplied to an option.


The program exited due to some error not otherwise described in this table.


Some internal software error occurred.


An error in the configuration file was detected.

7 How to Report a Bug

Email bug reports to gray+nssync@gnu.org.ua. Please include a detailed description of the bug and information about the conditions under which it occurs, so we can reproduce it. To facilitate the task, the following list shows the basic set of information that is needed in order to find the bug:


Latest release

Archive Size MD5 Signature
nssync-1.1.tar.gz 417K 24e25e1eac30708b004aa8477001739e nssync-1.1.tar.gz.sig
nssync-1.1.tar.xz 270K b5f067cbce014ef98737d5c36112a608 nssync-1.1.tar.xz.sig

You can use the signature file to verify that the corresponding file (without the .sig suffix) is intact. First, be sure to download both the .sig file and the corresponding tarball. Then, run a command like this:

  gpg --verify nssync-1.1.tar.gz.sig

If that command fails because you don't have the required public key, then run this command to import it:

  gpg --keyserver keys.gnupg.net --recv-keys 55D0C732

and rerun the `gpg --verify' command.

Other releases

This and older versions of NSSYNC can be downloaded from its ftp home.

You can keep track of the news and updates at the project's homepage.

Appendix A This Manual in Other Formats

The nssync manual is available in the following formats:

(This page is generated by the gendocs.sh script.)

Appendix B GNU Free Documentation License

Version 1.3, 3 November 2008
Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.

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    You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

    The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

    In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”


    You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

    You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.


    A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

    If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.


    Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

    If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.


    You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

    However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

    Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

    Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.


    The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http://www.gnu.org/copyleft/.

    Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.


    “Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.

    “CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

    “Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.

    An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.

    The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:

  Copyright (C)  year  your name.
  Permission is granted to copy, distribute and/or modify this document
  under the terms of the GNU Free Documentation License, Version 1.3
  or any later version published by the Free Software Foundation;
  with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
  Texts.  A copy of the license is included in the section entitled ``GNU
  Free Documentation License''.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:

    with the Invariant Sections being list their titles, with
    the Front-Cover Texts being list, and with the Back-Cover Texts
    being list.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.

Concept Index

This is a general index of all issues discussed in this manual.

Jump to:   #  
A   B   C   D   E   H   L   M   N   P   Q   R   S   T   U   Z  
Index Entry  Section
#include: Pragmatic Comments
#include_once: Pragmatic Comments
#line: Pragmatic Comments
add-statements: Synchronization Block
bind-include-path: General Settings
block statement: Statements
boolean value: Statements
check-ns: General Settings
Comments in a configuration file: Comments
comments, pragmatic: Pragmatic Comments
compare-command: General Settings
configuration file statements: Statements
database: SQL Access
escape sequence: Statements
here-document: Statements
host: SQL Access
list: Statements
m4: Preprocessor
multi-line comments: Comments
named-conf: General Settings
ns-query: Synchronization Block
nssync.conf: Configuration File
password: SQL Access
pidfile: General Settings
pp-setup: Preprocessor
pragmatic comments: Pragmatic Comments
preprocessor: Preprocessor
quoted string: Statements
reload-command: General Settings
rev-rr-query: Synchronization Block
rr-query: Synchronization Block
simple statements: Statements
single-line comments: Comments
slave-status-file: SQL Access
soa-query: Synchronization Block
sql-config-file: SQL Access
sql-config-group: SQL Access
ssl-ca: SQL Access
statement, block: Statements
statement, simple: Statements
statements, configuration file: Statements
string, quoted: Statements
string, unquoted: Statements
sync: Synchronization Block
synchronization block: Overview
synchronization block: Synchronization Block
synchronization tag: Synchronization Block
tempdir: General Settings
user: SQL Access
zone-conf: General Settings
zone-conf: Synchronization Block
zonefile-pattern: General Settings
zonefile-pattern: Synchronization Block
Jump to:   #  
A   B   C   D   E   H   L   M   N   P   Q   R   S   T   U   Z  



See http://bind-dlz.sourceforge.net/.


See: http://permalink.gmane.org/gmane.network.dns.bind9.dlz/2078, http://blog.gmane.org/gmane.network.dns.bind9.dlz/month=20110101.


As of version 1.1.91 only MySQL is supported.