README

BIND 9

	BIND version 9 is a major rewrite of nearly all aspects of the
	underlying BIND architecture.  Some of the important features of
	BIND 9 are:

		- DNS Security
			DNSSEC (signed zones)
			TSIG (signed DNS requests)

		- IP version 6
			Answers DNS queries on IPv6 sockets
			IPv6 resource records (AAAA)
			Experimental IPv6 Resolver Library

		- DNS Protocol Enhancements
			IXFR, DDNS, Notify, EDNS0
			Improved standards conformance

		- Views
			One server process can provide multiple "views" of
			the DNS namespace, e.g. an "inside" view to certain
			clients, and an "outside" view to others.

		- Multiprocessor Support

		- Improved Portability Architecture


	BIND version 9 development has been underwritten by the following
	organizations:

		Sun Microsystems, Inc.
		Hewlett Packard
		Compaq Computer Corporation
		IBM
		Process Software Corporation
		Silicon Graphics, Inc.
		Network Associates, Inc.
		U.S. Defense Information Systems Agency
		USENIX Association
		Stichting NLnet - NLnet Foundation
		Nominum, Inc.

	For a summary of functional enhancements in previous
	releases, see the HISTORY file.

	For a detailed list of user-visible changes from
	previous releases, see the CHANGES file.

	For up-to-date release notes and errata, see
	http://www.isc.org/software/bind9/releasenotes

BIND 9.11.0

	BIND 9.11.0 includes a number of changes from BIND 9.10 and earlier
	releases.  New features include:

	- Added support for Catalog Zones, a new method for provisioning
	  servers: a list of zones to be served is stored in a DNS zone,
	  along with their configuration parameters. Changes to the
	  catalog zone are propagated to slaves via normal AXFR/IXFR,
	  whereupon the zones that are listed in it are automatically
	  added, deleted or reconfigured.
	- Added support for "dnstap", a fast and flexible method of
	  capturing and logging DNS traffic.
	- Added support for "dyndb", a new API for loading zone data
	  from an external database, developed by Red Hat for the FreeIPA
	  project.
	- "fetchlimit" quotas are now compiled in by default.  These
          are for the use of recursive resolvers that are are under
          high query load for domains whose authoritative servers are
          nonresponsive or are experiencing a denial of service attack:
	  + "fetches-per-server" limits the number of simultaneous queries
	    that can be sent to any single authoritative server.  The
	    configured value is a starting point; it is automatically
	    adjusted downward if the server is partially or completely
	    non-responsive. The algorithm used to adjust the quota can be
	    configured via the "fetch-quota-params" option.
	  + "fetches-per-zone" limits the number of simultaneous queries
	    that can be sent for names within a single domain.  (Note:
	    Unlike "fetches-per-server", this value is not self-tuning.)
	  + New stats counters have been added to count
	    queries spilled due to these quotas.
	- Added a new "dnssec-keymgr" key mainenance utility, which can
	  generate or update keys as needed to ensure that a zone's
	  keys match a defined DNSSEC policy.
	- The experimental "SIT" feature in BIND 9.10 has been renamed
	  "COOKIE" and is no longer optional. EDNS COOKIE is a mechanism
	  enabling clients to detect off-path spoofed responses, and
	  servers to detect spoofed-source queries.  Clients that identify
	  themselves using COOKIE options are not subject to response rate
	  limiting (RRL) and can receive larger UDP responses.
	- SERVFAIL responses can now be cached for a limited time
	  (defaulting to 1 second, with an upper limit of 30).
	  This can reduce the frequency of retries when a query is
	  persistently failing.
	- Added an "nsip-wait-recurse" switch to RPZ. This causes NSIP
	  rules to be skipped if a name server IP address isn't in the
	  cache yet; the address will be looked up and the rule will be
	  applied on future queries.
	- Added a Python RNDC module. This allows multiple commands to
	  sent over a persistent RNDC channel, which saves time.
	- The "controls" block in named.conf can now grant read-only
	  "rndc" access to specified clients or keys. Read-only clients
	  could, for example, check "rndc status" but could not
	  reconfigure or shut down the server.
	- "rndc" commands can now return arbitrarily large amounts of
	  text to the caller.
	- The zone serial number of a dynamically updatable zone
	  can now be set via "rndc signing -serial <number> <zonename>".
	  This allows inline-signing zones to be set to a specific
	  serial number.
	- The new "rndc nta" command can be used to set a Negative
	  Trust Anchor (NTA), disabling DNSSEC validation for a
	  specific domain; this can be used when responses from a
	  domain are known to be failing validation due to administrative
	  error rather than because of a spoofing attack.  Negative
	  trust anchors are strictly temporary; by default they expire
	  after one hour, but can be configured to last up to one week.
	- "rndc delzone" can now be used on zones that were not originally
	  created by "rndc addzone".
	- "rndc modzone" reconfigures a single zone, without requiring
	  the entire server to be reconfigured.
	- "rndc showzone" displays the current configuration of a zone.
	- "rndc managed-keys" can be used to check the status of RFC 5001
	  managed trust anchors, or to force trust anchors to be refreshed.
	- "max-cache-size" can now be set to a percentage of available
	  memory. The default is 90%.
	- Update forwarding performance has been improved by allowing
	  a single TCP connection to be shared by multiple updates.
	- The EDNS Client Subnet (ECS) option is now supported for
	  authoritative servers; if a query contains an ECS option
	  then ACLs containing "geoip" or "ecs" elements can match
	  against the the address encoded in the option.  This can be
	  used to select a view for a query, so that different answers
	  can be provided depending on the client network.
	- The EDNS EXPIRE option has been implemented on the client
	  side, allowing a slave server to set the expiration timer
	  correctly when transferring zone data from another slave
	  server.
	- The key generation and manipulation tools (dnssec-keygen,
	  dnssec-settime, dnssec-importkey, dnssec-keyfromlabel) now
	  take "-Psync" and "-Dsync" options to set the publication
	  and deletion times of CDS and CDNSKEY parent-synchronization
	  records.  Both named and dnssec-signzone can now publish and
	  remove these records at the scheduled times.
	- A new "minimal-any" option reduces the size of UDP responses
	  for query type ANY by returning a single arbitrarily selected
	  RRset instead of all RRsets.
	- A new "masterfile-style" zone option controls the formatting
	  of text zone files:  When set to "full", a zone file is dumped
	  in single-line-per-record format.
	- "serial-update-method" can now be set to "date". On update,
	  the serial number will be set to the current date in YYYYMMDDNN
	  format.
	- "dnssec-signzone -N date" sets the serial number to YYYYMMDDNN.
	- "named -L <filename>" causes named to send log messages to
	   the specified file by default instead of to the system log.
	- "dig +ttlunits" prints TTL values with time-unit suffixes:
	  w, d, h, m, s for weeks, days, hours, minutes, and seconds.
	- "dig +unknownformat" prints dig output in RFC 3597 "unknown
	  record" presentation format.
	- "dig +ednsopt" allows dig to set arbitrary EDNS options on
	  requests.
	- "dig +ednsflags" allows dig to set yet-to-be-defined EDNS
	  flags on requests.
	- "mdig" is an alternate version of dig which sends multiple
	  pipelined TCP queries to a server.  Instead of waiting for a
	  response after sending a query, it sends all queries
	  immediately and displays responses in the order received.
	- "serial-query-rate" no longer controls NOTIFY messages.
	  These are separately controlled by "notify-rate" and
	  "startup-notify-rate".
	- "nsupdate" now performs "check-names" processing by default
	  on records to be added.  This can be disabled with
	  "check-names no".
	- The statistics channel now supports DEFLATE compression,
	  reducing the size of the data sent over the network when
	  querying statistics.
	- New counters have been added to the statistics channel
	  to track the sizes of incoming queries and outgoing responses in
	  histogram buckets, as specified in RSSAC002.
	- A new NXDOMAIN redirect method (option "nxdomain-redirect")
	  has been added, allowing redirection to a specified DNS
	  namespace instead of a single redirect zone.
	- When starting up, named now ensures that no other named
	  process is already running.
	- Files created by named to store information, including "mkeys"
	  and "nzf" files, are now named after their corresponding views
	  unless the view name contains characters incompatible with use
	  as a filename. Old style filenames (based on the hash of the
	  view name) will still work.

	This release addresses the security flaws described in
	CVE-2014-3214, CVE-2014-3859, CVE-2014-8500, CVE-2014-8680,
	CVE-2015-1349, CVE-2015-5477, CVE-2015-5722, CVE-2015-5986,
	CVE-2015-8000, CVE-2015-8704, CVE-2015-8705, CVE-2016-1285,
	CVE-2016-1286, CVE-2016-2088 and CVE-2016-2775.

Building

	BIND 9 currently requires a UNIX system with an ANSI C compiler,
	basic POSIX support, and a 64 bit integer type.

	We've had successful builds and tests on the following systems:

		COMPAQ Tru64 UNIX 5.1B
		Fedora Core 6
		FreeBSD 4.10, 5.2.1, 6.2
		HP-UX 11.11
		Mac OS X 10.5
		NetBSD 3.x, 4.0-beta, 5.0-beta
		OpenBSD 3.3 and up
		Solaris 8, 9, 9 (x86), 10
		Ubuntu 7.04, 7.10
		Windows XP/2003/2008

	NOTE:  As of BIND 9.5.1, 9.4.3, and 9.3.6, older versions of
	Windows, including Windows NT and Windows 2000, are no longer
	supported.

	We have recent reports from the user community that a supported
	version of BIND will build and run on the following systems:

		AIX 4.3, 5L
		CentOS 4, 4.5, 5
		Darwin 9.0.0d1/ARM
		Debian 4, 5, 6
		Fedora Core 5, 7, 8
		FreeBSD 6, 7, 8
		HP-UX 11.23 PA
		MacOS X 10.5, 10.6, 10.7
		Red Hat Enterprise Linux 4, 5, 6
		SCO OpenServer 5.0.6
		Slackware 9, 10
		SuSE 9, 10

	To build, just

		./configure
		make

	Do not use a parallel "make".

	Several environment variables that can be set before running
	configure will affect compilation:

	    CC
		The C compiler to use.  configure tries to figure
		out the right one for supported systems.

	    CFLAGS
		C compiler flags.  Defaults to include -g and/or -O2
		as supported by the compiler.  Please include '-g'
		if you need to set CFLAGS.

	    STD_CINCLUDES
		System header file directories.  Can be used to specify
		where add-on thread or IPv6 support is, for example.
		Defaults to empty string.

	    STD_CDEFINES
		Any additional preprocessor symbols you want defined.
		Defaults to empty string.

		Possible settings:
		Change the default syslog facility of named/lwresd.
		  -DISC_FACILITY=LOG_LOCAL0
		Enable DNSSEC signature chasing support in dig.
		  -DDIG_SIGCHASE=1 (sets -DDIG_SIGCHASE_TD=1 and
				    -DDIG_SIGCHASE_BU=1)
		Disable dropping queries from particular well known ports.
		  -DNS_CLIENT_DROPPORT=0
		Sibling glue checking in named-checkzone is enabled by default.
		To disable the default check set.  -DCHECK_SIBLING=0
		named-checkzone checks out-of-zone addresses by default.
		To disable this default set.  -DCHECK_LOCAL=0
		To create the default pid files in ${localstatedir}/run rather
		than ${localstatedir}/run/{named,lwresd}/ set.
		  -DNS_RUN_PID_DIR=0
		Enable workaround for Solaris kernel bug about /dev/poll
		  -DISC_SOCKET_USE_POLLWATCH=1
		  The watch timeout is also configurable, e.g.,
		  -DISC_SOCKET_POLLWATCH_TIMEOUT=20

	    LDFLAGS
		Linker flags. Defaults to empty string.

	The following need to be set when cross compiling.

	    BUILD_CC
		The native C compiler.
	    BUILD_CFLAGS (optional)
	    BUILD_CPPFLAGS (optional)
		Possible Settings:
		-DNEED_OPTARG=1         (optarg is not declared in <unistd.h>)
	    BUILD_LDFLAGS (optional)
	    BUILD_LIBS (optional)

	On most platforms, BIND 9 is built with multithreading
	support, allowing it to take advantage of multiple CPUs.
	You can configure this by specifying "--enable-threads" or
	"--disable-threads" on the configure command line.  The default
	is to enable threads, except on some older operating systems
	on which threads are known to have had problems in the past.
	(Note: Prior to BIND 9.10, the default was to disable threads on
	Linux systems; this has been reversed.  On Linux systems, the
	threaded build is known to change BIND's behavior with respect
	to file permissions; it may be necessary to specify a user with
	the -u option when running named.)

	To build shared libraries, specify "--with-libtool" on the
	configure command line.

	Certain compiled-in constants and default settings can be
	increased to values better suited to large servers with abundant
	memory resources (e.g, 64-bit servers with 12G or more of memory)
	by specifying "--with-tuning=large" on the configure command
	line. This can improve performance on big servers, but will
	consume more memory and may degrade performance on smaller
	systems.

	For the server to support DNSSEC, you need to build it
	with crypto support.  You must have OpenSSL 0.9.5a
	or newer installed and specify "--with-openssl" on the
	configure command line.  If OpenSSL is installed under
	a nonstandard prefix, you can tell configure where to
	look for it using "--with-openssl=/prefix".

	To support the HTTP statistics channel, the server must
	be linked with at least one of the following: libxml2
	(http://xmlsoft.org) or json-c (https://github.com/json-c).
	If these are installed at a nonstandard prefix, use
	"--with-libxml2=/prefix" or "--with-libjson=/prefix".

	To support compression on the HTTP statistics channel, the
	server must be linked against libzlib (--with-zlib=/prefix).

	Python requires 'argparse' and 'ply' to be available.
	'argparse' is a standard module as of Python 2.7 and Python 3.2.

	On some platforms it is necessary to explicitly request large
	file support to handle files bigger than 2GB.  This can be
	done by "--enable-largefile" on the configure command line.

	Support for the "fixed" rrset-order option can be enabled
	or disabled by specifying "--enable-fixed-rrset" or
	"--disable-fixed-rrset" on the configure command line.
	The default is "disabled", to reduce memory footprint.

	If your operating system has integrated support for IPv6, it
	will be used automatically.  If you have installed KAME IPv6
	separately, use "--with-kame[=PATH]" to specify its location.

	"make install" will install "named" and the various BIND 9 libraries.
	By default, installation is into /usr/local, but this can be changed
	with the "--prefix" option when running "configure".

	You may specify the option "--sysconfdir" to set the directory
	where configuration files like "named.conf" go by default,
	and "--localstatedir" to set the default parent directory
	of "run/named.pid".   For backwards compatibility with BIND 8,
	--sysconfdir defaults to "/etc" and --localstatedir defaults to
	"/var" if no --prefix option is given.  If there is a --prefix
	option, sysconfdir defaults to "$prefix/etc" and localstatedir
	defaults to "$prefix/var".

	To see additional configure options, run "configure --help".
	Note that the help message does not reflect the BIND 8
	compatibility defaults for sysconfdir and localstatedir.

	If you're planning on making changes to the BIND 9 source, you
	should also "make depend".  If you're using Emacs, you might find
	"make tags" helpful.

	If you need to re-run configure please run "make distclean" first.
	This will ensure that all the option changes take.

	Building with gcc is not supported, unless gcc is the vendor's usual
	compiler (e.g. the various BSD systems, Linux).

	Known compiler issues:
	* gcc-3.2.1 and gcc-3.1.1 is known to cause problems with solaris-x86.
	* gcc prior to gcc-3.2.3 ultrasparc generates incorrect code at -02.
	* gcc-3.3.5 powerpc generates incorrect code at -02.
	* Irix, MipsPRO 7.4.1m is known to cause problems.

	A limited test suite can be run with "make test".  Many of
	the tests require you to configure a set of virtual IP addresses
	on your system, and some require Perl; see bin/tests/system/README
	for details.

	SunOS 4 requires "printf" to be installed to make the shared
	libraries.  sh-utils-1.16 provides a "printf" which compiles
	on SunOS 4.

Known limitations

	Linux requires kernel build 2.6.39 or later to get the
	performance benefits from using multiple sockets.

Documentation

	The BIND 9 Administrator Reference Manual is included with the
	source distribution in DocBook XML and HTML format, in the
	doc/arm directory.

	Some of the programs in the BIND 9 distribution have man pages
	in their directories.  In particular, the command line
	options of "named" are documented in /bin/named/named.8.
	There is now also a set of man pages for the lwres library.

	If you are upgrading from BIND 8, please read the migration
	notes in doc/misc/migration.  If you are upgrading from
	BIND 4, read doc/misc/migration-4to9.

	Frequently asked questions and their answers can be found in
	FAQ.

	Additional information on various subjects can be found
	in the other README files.


Change Log

	A detailed list of all changes to BIND 9 is included in the
	file CHANGES, with the most recent changes listed first.
	Change notes include tags indicating the category of the
	change that was made; these categories are:

	   [func]         New feature

	   [bug]          General bug fix

	   [security]     Fix for a significant security flaw

	   [experimental] Used for new features when the syntax
			  or other aspects of the design are still
			  in flux and may change

	   [port]         Portability enhancement

	   [maint]        Updates to built-in data such as root
			  server addresses and keys

	   [tuning]       Changes to built-in configuration defaults
			  and constants to improve performance

	   [performance]  Other changes to improve server performance

	   [protocol]     Updates to the DNS protocol such as new
			  RR types

	   [test]         Changes to the automatic tests, not
			  affecting server functionality

	   [cleanup]      Minor corrections and refactoring

	   [doc]          Documentation

	   [contrib]	  Changes to the contributed tools and
			  libraries in the 'contrib' subdirectory

	   [placeholder]  Used in the master development branch to
			  reserve change numbers for use in other
			  branches, e.g. when fixing a bug that only
			  exists in older releases

	In general, [func] and [experimental] tags will only appear
	in new-feature releases (i.e., those with version numbers
	ending in zero).  Some new functionality may be backported to
	older releases on a case-by-case basis.  All other change
	types may be applied to all currently-supported releases.


Bug Reports and Mailing Lists

	Bug reports should be sent to:

		bind9-bugs@isc.org

	Feature requests can be sent to:

		bind-suggest@isc.org

	To join or view the archives of the BIND Users mailing list,
	visit:

		https://lists.isc.org/mailman/listinfo/bind-users

	If you're planning on making changes to the BIND 9 source
	code, you may also want to join the BIND Workers mailing
	list:

		https://lists.isc.org/mailman/listinfo/bind-workers

	Information on read-only Git access, coding style and developer
	guidelines can be found at:

		http://www.isc.org/git/


Acknowledgments

	- This product includes software developed by the OpenSSL Project
	  for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/).
	- This product includes cryptographic software written by Eric
	  Young (eay@cryptsoft.com).
	- This product includes software written by Tim Hudson
	  (tjh@cryptsoft.com).