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doc/ 2016-04-07 06:28 -
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 "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.
- New "fetchlimit" quotas are now available 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.
- 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.
- 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 "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 and CVE-2016-2088.
BIND 9.10.0
BIND 9.10.0 includes a number of changes from BIND 9.9 and earlier
releases. New features include:
- DNS Response-rate limiting (DNS RRL), which blunts the
impact of reflection and amplification attacks, is always
compiled in and no longer requires a compile-time option
to enable it.
- An experimental "Source Identity Token" (SIT) EDNS option
is now available. Similar to DNS Cookies as invented by
Donald Eastlake 3rd, these are designed to enable clients
to detect off-path spoofed responses, and to enable servers
to detect spoofed-source queries. Servers can be configured
to send smaller responses to clients that have not identified
themselves using a SIT option, reducing the effectiveness of
amplification attacks. RRL processing has also been updated;
clients proven to be legitimate via SIT are not subject to
rate limiting. Use "configure --enable-sit" to enable this
feature in BIND.
- A new zone file format, "map", stores zone data in a
format that can be mapped directly into memory, allowing
significantly faster zone loading.
- "delv" (domain entity lookup and validation) is a new tool
with dig-like semantics for looking up DNS data and performing
internal DNSSEC validation. This allows easy validation in
environments where the resolver may not be trustworthy, and
assists with troubleshooting of DNSSEC problems. (NOTE:
In previous development releases of BIND 9.10, this utility
was called "delve". The spelling has been changed to avoid
confusion with the "delve" utility included with the Xapian
search engine.)
- Improved EDNS(0) processing for better resolver performance
and reliability over slow or lossy connections.
- A new "configure --with-tuning=large" option tunes certain
compiled-in constants and default settings to values better
suited to large servers with abundant memory. This can
improve performance on such servers, but will consume more
memory and may degrade performance on smaller systems.
- Substantial improvement in response-policy zone (RPZ)
performance. Up to 32 response-policy zones can be
configured with minimal performance loss.
- To improve recursive resolver performance, cache records
which are still being requested by clients can now be
automatically refreshed from the authoritative server
before they expire, reducing or eliminating the time
window in which no answer is available in the cache.
- New "rpz-client-ip" triggers and drop policies allowing
response policies based on the IP address of the client.
- ACLs can now be specified based on geographic location
using the MaxMind GeoIP databases. Use "configure
--with-geoip" to enable.
- Zone data can now be shared between views, allowing
multiple views to serve the same zones authoritatively
without storing multiple copies in memory.
- New XML schema (version 3) for the statistics channel
includes many new statistics and uses a flattened XML tree
for faster parsing. The older schema is now deprecated.
- A new stylesheet, based on the Google Charts API, displays
XML statistics in charts and graphs on javascript-enabled
browsers.
- The statistics channel can now provide data in JSON
format as well as XML.
- New stats counters track TCP and UDP queries received
per zone, and EDNS options received in total.
- The internal and export versions of the BIND libraries
(libisc, libdns, etc) have been unified so that external
library clients can use the same libraries as BIND itself.
- A new compile-time option, "configure --enable-native-pkcs11",
allows BIND 9 cryptography functions to use the PKCS#11 API
natively, so that BIND can drive a cryptographic hardware
service module (HSM) directly instead of using a modified
OpenSSL as an intermediary. (Note: This feature requires an
HSM to have a full implementation of the PKCS#11 API; many
current HSMs only have partial implementations. The new
"pkcs11-tokens" command can be used to check API completeness.
Native PKCS#11 is known to work with the Thales nShield HSM
and with SoftHSM version 2 from the Open DNSSEC project.)
- The new "max-zone-ttl" option enforces maximum TTLs for
zones. This can simplify the process of rolling DNSSEC keys
by guaranteeing that cached signatures will have expired
within the specified amount of time.
- "dig +subnet" sends an EDNS CLIENT-SUBNET option when
querying.
- "dig +expire" sends an EDNS EXPIRE option when querying.
When this option is sent with an SOA query to a server
that supports it, it will report the expiry time of
a slave zone.
- New "dnssec-coverage" tool to check DNSSEC key coverage
for a zone and report if a lapse in signing coverage has
been inadvertently scheduled.
- Signing algorithm flexibility and other improvements
for the "rndc" control channel.
- "named-checkzone" and "named-compilezone" can now read
journal files, allowing them to process dynamic zones.
- Multiple DLZ databases can now be configured. Individual
zones can be configured to be served from a specific DLZ
database. DLZ databases now serve zones of type "master"
and "redirect".
- "rndc zonestatus" reports information about a specified zone.
- "named" now listens on IPv6 as well as IPv4 interfaces
by default.
- "named" now preserves the capitalization of names
when responding to queries: for instance, a query for
"example.com" may be answered with "example.COM" if the
name was configured that way in the zone file. Some
clients have a bug causing them to depend on the older
behavior, in which the case of the answer always matched
the case of the query, rather than the case of the name
configured in the DNS. Such clients can now be specified
in the new "no-case-compress" ACL; this will restore the
older behavior of "named" for those clients only.
- new "dnssec-importkey" command allows the use of offline
DNSSEC keys with automatic DNSKEY management.
- New "named-rrchecker" tool to verify the syntactic
correctness of individual resource records.
- When re-signing a zone, the new "dnssec-signzone -Q" option
drops signatures from keys that are still published but are
no longer active.
- "named-checkconf -px" will print the contents of configuration
files with the shared secrets obscured, making it easier to
share configuration (e.g. when submitting a bug report)
without revealing private information.
- "rndc scan" causes named to re-scan network interfaces for
changes in local addresses.
- On operating systems with support for routing sockets,
network interfaces are re-scanned automatically whenever
they change.
- "tsig-keygen" is now available as an alternate command
name to use for "ddns-confgen".
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).
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).