<
div class="titlepage"><
div><
div><
h3 class="title">
<
a name="relnotes_security"></
a>Security Fixes</
h3></
div></
div></
div>
<
div class="itemizedlist"><
ul class="itemizedlist" style="list-style-type: disc; "><
li class="listitem"><
p>
getrrsetbyname with a non absolute name could trigger a
infinite recursion bug in lwresd and named with lwres
configured if when combined with a search list entry the
resulting name is too long. This issue is disclosed in
<
div class="titlepage"><
div><
div><
h3 class="title">
<
a name="relnotes_features"></
a>New Features</
h3></
div></
div></
div>
<
div class="itemizedlist"><
ul class="itemizedlist" style="list-style-type: disc; ">
A new method of provisioning secondary servers called
"Catalog Zones" has been added. This is an implementation of
draft-muks-dnsop-dns-catalog-zones/
A catalog zone is a regular DNS zone which contains a list
of "member zones", along with the configuration options for
each of those zones. When a server is configured to use a
catalog zone, all the zones listed in the catalog zone are
added to the local server as slave zones. When the catalog
zone is updated (
e.g., by adding or removing zones, or
changing configuration options for existing zones) those
changes will be put into effect. Since the catalog zone is
itself a DNS zone, this means configuration changes can be
propagated to slaves using the standard
AXFR/
IXFR update
This feature should be considered experimental. It currently
supports only basic features; more advanced features such as
ACLs and TSIG keys are not yet supported. Example catalog
zone configurations can be found in the Chapter 9 of the
BIND Administrator Reference Manual.
Support for master entries with TSIG keys has been added to catalog
zones, as well as support for allow-query and allow-transfer.
Added rndc python module.
Added support for DynDB, a new interface for loading zone data
from an external database, developed by Red Hat for the FreeIPA
project. (Thanks in particular to Adam Tkac and Petr
Spacek of Red Hat for the contribution.)
Unlike the existing DLZ and SDB interfaces, which provide a
limited subset of database functionality within BIND —
translating DNS queries into real-time database lookups with
relatively poor performance and with no ability to handle
DNSSEC-signed data — DynDB is able to fully implement
and extend the database API used natively by BIND.
A DynDB module could pre-load data from an external data
source, then serve it with the same performance and
functionality as conventional BIND zones, and with the
ability to take advantage of database features not
available in BIND, such as multi-master replication.
New quotas have been added to limit the queries that are
sent by recursive resolvers to authoritative servers
experiencing denial-of-service attacks. When configured,
these options can both reduce the harm done to authoritative
servers and also avoid the resource exhaustion that can be
experienced by recursive servers when they are being used as a
vehicle for such an attack.
<
div class="itemizedlist"><
ul class="itemizedlist" style="list-style-type: circle; ">
<
code class="option">fetches-per-server</
code> 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
<
code class="option">fetch-quota-params</
code> option.
<
code class="option">fetches-per-zone</
code> 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.)
Statistics counters have also been added to track the number
of queries affected by these quotas.
Added support for <
span class="command"><
strong>dnstap</
strong></
span>, a fast,
flexible method for capturing and logging DNS traffic,
developed by Robert Edmonds at Farsight Security, Inc.,
whose assistance is gratefully acknowledged.
To enable <
span class="command"><
strong>dnstap</
strong></
span> at compile time,
the <
span class="command"><
strong>fstrm</
strong></
span> and <
span class="command"><
strong>protobuf-c</
strong></
span>
libraries must be available, and BIND must be configured with
<
code class="option">--enable-dnstap</
code>.
A new utility <
span class="command"><
strong>dnstap-read</
strong></
span> has been added
to allow <
span class="command"><
strong>dnstap</
strong></
span> data to be presented in
<
span class="command"><
strong>rndc dnstap-reopen</
strong></
span> can be used reopen
dnstap output files after renaming them.
For more information on <
span class="command"><
strong>dnstap</
strong></
span>, see
New statistics counters have been added to track traffic
sizes, as specified in RSSAC002. Query and response
message sizes are broken up into ranges of histogram buckets:
TCP and UDP queries of size 0-15, 16-31, ..., 272-288, and 288+,
and TCP and UDP responses of size 0-15, 16-31, ..., 4080-4095,
and 4096+. These values can be accessed via the XML and JSON
statistics channels at, for example,
Statistics for RSSAC02v3 traffic-volume, traffic-sizes and
rcode-volume reporting are now collected.
A new DNSSEC key management utility,
<
span class="command"><
strong>dnssec-keymgr</
strong></
span>, has been added. This tool
is meant to run unattended (
e.g., under <
span class="command"><
strong>cron</
strong></
span>).
It reads a policy definition file
and creates or updates DNSSEC keys as necessary to ensure that a
zone's keys match the defined policy for that zone. New keys are
created whenever necessary to ensure rollovers occur correctly.
Existing keys' timing metadata is adjusted as needed to set the
correct rollover period, prepublication interval, etc. If
the configured policy changes, keys are corrected automatically.
See the <
span class="command"><
strong>dnssec-keymgr</
strong></
span> man page for full details.
Note: <
span class="command"><
strong>dnssec-keymgr</
strong></
span> depends on Python and on
the Python
lex/
yacc module, PLY. The other Python-based tools,
<
span class="command"><
strong>dnssec-coverage</
strong></
span> and
<
span class="command"><
strong>dnssec-checkds</
strong></
span>, have been
refactored and updated as part of this work.
<
span class="command"><
strong>dnssec-keymgr</
strong></
span> now takes a -r
<
em class="replaceable"><
code>randomfile</
code></
em> option.
(Many thanks to Sebasti�n
Castro for his assistance in developing this tool at the IETF
95 Hackathon in Buenos Aires, April 2016.)
The serial number of a dynamically updatable zone can
<
span class="command"><
strong>rndc signing -serial <
em class="replaceable"><
code>number</
code></
em> <
em class="replaceable"><
code>zonename</
code></
em></
strong></
span>.
This is particularly useful with <
code class="option">inline-signing</
code>
zones that have been reset. Setting the serial number to a value
larger than that on the slaves will trigger an AXFR-style
When answering recursive queries, SERVFAIL responses can now be
cached by the server for a limited time; subsequent queries for
the same query name and type will return another SERVFAIL until
the cache times out. This reduces the frequency of retries
when a query is persistently failing, which can be a burden
on recursive servers. The SERVFAIL cache timeout is controlled
by <
code class="option">servfail-ttl</
code>, which defaults to 1 second
and has an upper limit of 30.
The new <
span class="command"><
strong>rndc nta</
strong></
span> command can now 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. NTAs are strictly
temporary; by default they expire after one hour, but can be
configured to last up to one week. The default NTA lifetime
can be changed by setting the <
code class="option">nta-lifetime</
code> in
<
code class="filename">
named.conf</
code>. When added, NTAs are stored in a
file (<
code class="filename"><
em class="replaceable"><
code>viewname</
code></
em>.nta</
code>)
in order to persist across restarts of the <
span class="command"><
strong>named</
strong></
span> server.
The EDNS Client Subnet (ECS) option is now supported for
authoritative servers; if a query contains an ECS option then
ACLs containing <
code class="option">geoip</
code> or <
code class="option">ecs</
code>
elements can match against 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
A new <
code class="option">masterfile-style</
code> zone option controls
the formatting of text zone files: When set to
<
code class="literal">full</
code>, the zone file will dumped in
single-line-per-record format.
<
span class="command"><
strong>dig +ednsopt</
strong></
span> can now be used to set
arbitrary EDNS options in DNS requests.
<
span class="command"><
strong>dig +ednsflags</
strong></
span> can now be used to set
yet-to-be-defined EDNS flags in DNS requests.
<
span class="command"><
strong>dig +[no]ednsnegotiation</
strong></
span> can now be used enable /
disable EDNS version negotiation.
<
span class="command"><
strong>dig +header-only</
strong></
span> can now be used to send
queries without a question section.
<
span class="command"><
strong>dig +ttlunits</
strong></
span> causes <
span class="command"><
strong>dig</
strong></
span>
to print TTL values with time-unit suffixes: w, d, h, m, s for
weeks, days, hours, minutes, and seconds.
<
span class="command"><
strong>dig +zflag</
strong></
span> can be used to set the last
unassigned DNS header flag bit. This bit is normally zero.
<
span class="command"><
strong>dig +dscp=<
em class="replaceable"><
code>value</
code></
em></
strong></
span>
can now be used to set the DSCP code point in outgoing query
<
span class="command"><
strong>dig +mapped</
strong></
span> can now be used to determine
if mapped IPv4 addresses can be used.
<
code class="option">serial-update-method</
code> can now be set to
<
code class="literal">date</
code>. On update, the serial number will
be set to the current date in YYYYMMDDNN format.
<
span class="command"><
strong>dnssec-signzone -N date</
strong></
span> also sets the serial
<
span class="command"><
strong>named -L <
em class="replaceable"><
code>filename</
code></
em></
strong></
span>
causes <
span class="command"><
strong>named</
strong></
span> to send log messages to the
specified file by default instead of to the system log.
The rate limiter configured by the
<
code class="option">serial-query-rate</
code> option no longer covers
NOTIFY messages; those are now separately controlled by
<
code class="option">notify-rate</
code> and
<
code class="option">startup-notify-rate</
code> (the latter of which
controls the rate of NOTIFY messages sent when the server
is first started up or reconfigured).
The default number of tasks and client objects available
for serving lightweight resolver queries have been increased,
and are now configurable via the new <
code class="option">lwres-tasks</
code>
and <
code class="option">lwres-clients</
code> options in
<
code class="filename">
named.conf</
code>. [RT #35857]
Log output to files can now be buffered by specifying
<
span class="command"><
strong>buffered yes;</
strong></
span> when creating a channel.
<
span class="command"><
strong>delv +tcp</
strong></
span> will exclusively use TCP when
<
span class="command"><
strong>named</
strong></
span> will now check to see whether
other name server processes are running before starting up.
This is implemented in two ways: 1) by refusing to start
if the configured network interfaces all return "address
in use", and 2) by attempting to acquire a lock on a file
specified by the <
code class="option">lock-file</
code> option or
the <
span class="command"><
strong>-X</
strong></
span> command line option. The
Specifying <
code class="literal">none</
code> will disable the lock
<
span class="command"><
strong>rndc delzone</
strong></
span> can now be applied to zones
which were configured in <
code class="filename">
named.conf</
code>;
it is no longer restricted to zones which were added by
<
span class="command"><
strong>rndc addzone</
strong></
span>. (Note, however, that
this does not edit <
code class="filename">
named.conf</
code>; the zone
must be removed from the configuration or it will return
when <
span class="command"><
strong>named</
strong></
span> is restarted or reloaded.)
<
span class="command"><
strong>rndc modzone</
strong></
span> can be used to reconfigure
a zone, using similar syntax to <
span class="command"><
strong>rndc addzone</
strong></
span>.
<
span class="command"><
strong>rndc showzone</
strong></
span> displays the current
configuration for a specified zone.
Added server-side support for pipelined TCP queries. Clients
may continue sending queries via TCP while previous queries are
processed in parallel. Responses are sent when they are
ready, not necessarily in the order in which the queries were
To revert to the former behavior for a particular
client address or range of addresses, specify the address prefix
in the "keep-response-order" option. To revert to the former
behavior for all clients, use "keep-response-order { any; };".
The new <
span class="command"><
strong>mdig</
strong></
span> command is a version of
<
span class="command"><
strong>dig</
strong></
span> that sends multiple pipelined
queries and then waits for responses, instead of sending one
query and waiting the response before sending the next. [RT #38261]
To enable better monitoring and troubleshooting of RFC 5011
trust anchor management, the new <
span class="command"><
strong>rndc managed-keys</
strong></
span>
can be used to check status of trust anchors or to force keys
to be refreshed. Also, the managed-keys data file now has
easier-to-read comments. [RT #38458]
An <
span class="command"><
strong>--enable-querytrace</
strong></
span> configure switch is
now available to enable very verbose query tracelogging. This
option can only be set at compile time. This option has a
negative performance impact and should be used only for
A new <
span class="command"><
strong>tcp-only</
strong></
span> option can be specified
in <
span class="command"><
strong>server</
strong></
span> statements to force
<
span class="command"><
strong>named</
strong></
span> to connect to the specified
server via TCP. [RT #37800]
The <
span class="command"><
strong>nxdomain-redirect</
strong></
span> option specifies
a DNS namespace to use for NXDOMAIN redirection. When a
recursive lookup returns NXDOMAIN, a second lookup is
initiated with the specified name appended to the query
name. This allows NXDOMAIN redirection data to be supplied
by multiple zones configured on the server or by recursive
queries to other servers. (The older method, using
a single <
span class="command"><
strong>type redirect</
strong></
span> zone, has
better average performance but is less flexible.) [RT #37989]
The following types have been implemented: CSYNC, NINFO, RKEY,
A new <
span class="command"><
strong>message-compression</
strong></
span> option can be
used to specify whether or not to use name compression when
answering queries. Setting this to <
strong class="userinput"><
code>no</
code></
strong>
results in larger responses, but reduces CPU consumption and
may improve throughput. The default is <
strong class="userinput"><
code>yes</
code></
strong>.
A <
span class="command"><
strong>read-only</
strong></
span> option is now available in the
<
span class="command"><
strong>controls</
strong></
span> statement to grant non-destructive
control channel access. In such cases, a restricted set of
<
span class="command"><
strong>rndc</
strong></
span> commands are allowed, which can
report information from <
span class="command"><
strong>named</
strong></
span>, but cannot
reconfigure or stop the server. By default, the control channel
access is <
span class="emphasis"><
em>not</
em></
span> restricted to these
read-only operations. [RT #40498]
When loading a signed zone, <
span class="command"><
strong>named</
strong></
span> will
now check whether an RRSIG's inception time is in the future,
and if so, it will regenerate the RRSIG immediately. This helps
when a system's clock needs to be reset backwards.
The new <
span class="command"><
strong>minimal-any</
strong></
span> option reduces the size
of answers to UDP queries for type ANY by implementing one of
the strategies in "draft-ietf-dnsop-refuse-any": returning
a single arbitrarily-selected RRset that matches the query
name rather than returning all of the matching RRsets.
Thanks to Tony Finch for the contribution. [RT #41615]
<
div class="titlepage"><
div><
div><
h3 class="title">
<
a name="relnotes_changes"></
a>Feature Changes</
h3></
div></
div></
div>
<
div class="itemizedlist"><
ul class="itemizedlist" style="list-style-type: disc; ">
The ISC DNSSEC Lookaside Validation (DLV) service is scheduled
to be disabled in 2017. A warning is now logged when
<
span class="command"><
strong>named</
strong></
span> is configured to use this service,
either explicitly or via <
code class="option">dnssec-lookaside auto;</
code>.
The timers returned by the statistics channel (indicating current
time, server boot time, and most recent reconfiguration time) are
now reported with millisecond accuracy. [RT #40082]
ACLs containing <
span class="command"><
strong>geoip asnum</
strong></
span> elements were
not correctly matched unless the full organization name was
specified in the ACL (as in
<
span class="command"><
strong>geoip asnum "AS1234 Example, Inc.";</
strong></
span>).
They can now match against the AS number alone (as in
<
span class="command"><
strong>geoip asnum "AS1234";</
strong></
span>).
When using native PKCS#11 cryptography (
i.e.,
<
span class="command"><
strong>configure --enable-native-pkcs11</
strong></
span>) HSM PINs
of up to 256 characters can now be used.
NXDOMAIN responses to queries of type DS are now cached separately
from those for other types. This helps when using "grafted" zones
of type forward, for which the parent zone does not contain a
delegation, such as local top-level domains. Previously a query
of type DS for such a zone could cause the zone apex to be cached
as NXDOMAIN, blocking all subsequent queries. (Note: This
change is only helpful when DNSSEC validation is not enabled.
"Grafted" zones without a delegation in the parent are not a
recommended configuration.)
Update forwarding performance has been improved by allowing
a single TCP connection to be shared between multiple updates.
By default, <
span class="command"><
strong>nsupdate</
strong></
span> will now check
the correctness of hostnames when adding records of type
A, AAAA, MX, SOA, NS, SRV or PTR. This behavior can be
disabled with <
span class="command"><
strong>check-names no</
strong></
span>.
Added support for OPENPGPKEY type.
The names of the files used to store managed keys and added
zones for each view are no longer based on the SHA256 hash
of the view name, except when this is necessary because the
view name contains characters that would be incompatible with use
as a file name. For views whose names do not contain forward
slashes ('/'), backslashes ('\'), or capital letters - which
could potentially cause namespace collision problems on
case-insensitive filesystems - files will now be named
after the view (for example, <
code class="filename">
internal.mkeys</
code>
or <
code class="filename">
external.nzf</
code>). However, to ensure
consistent behavior when upgrading, if a file using the old
name format is found to exist, it will continue to be used.
"rndc" can now return text output of arbitrary size to
the caller. (Prior to this, certain commands such as
"rndc tsig-list" and "rndc zonestatus" could return
Errors reported when running <
span class="command"><
strong>rndc addzone</
strong></
span>
(
e.g., when a zone file cannot be loaded) have been clarified
to make it easier to diagnose problems.
When encountering an authoritative name server whose name is
an alias pointing to another name, the resolver treats
this as an error and skips to the next server. Previously
this happened silently; now the error will be logged to
the newly-created "cname" log category.
If <
span class="command"><
strong>named</
strong></
span> is not configured to validate
answers, then allow fallback to plain DNS on timeout even when
we know the server supports EDNS. This will allow the server to
potentially resolve signed queries when TCP is being
Large inline-signing changes should be less disruptive.
Signature generation is now done incrementally; the number
of signatures to be generated in each quantum is controlled
by "sig-signing-signatures <
em class="replaceable"><
code>number</
code></
em>;".
The experimental SIT option (code point 65001) of BIND
9.10.0 through BIND 9.10.2 has been replaced with the COOKIE
option (code point 10). It is no longer experimental, and
is sent by default, by both <
span class="command"><
strong>named</
strong></
span> and
<
span class="command"><
strong>dig</
strong></
span>.
The SIT-related
named.conf options have been marked as
obsolete, and are otherwise ignored.
When <
span class="command"><
strong>dig</
strong></
span> receives a truncated (TC=1)
response or a BADCOOKIE response code from a server, it
will automatically retry the query using the server COOKIE
that was returned by the server in its initial response.
A alternative NXDOMAIN redirect method (nxdomain-redirect)
which allows the redirect information to be looked up from
a namespace on the Internet rather than requiring a zone
to be configured on the server is now available.
on Linux is now supported.
A new <
code class="option">nsip-wait-recurse</
code> directive has been
added to RPZ, specifying whether to look up unknown name server
IP addresses and wait for a response before applying RPZ-NSIP rules.
The default is <
strong class="userinput"><
code>yes</
code></
strong>. If set to
<
strong class="userinput"><
code>no</
code></
strong>, <
span class="command"><
strong>named</
strong></
span> will only
apply RPZ-NSIP rules to servers whose addresses are already cached.
The addresses will be looked up in the background so the rule can
be applied on subsequent queries. This improves performance when
the cache is cold, at the cost of temporary imprecision in applying
policy directives. [RT #35009]
Within the <
code class="option">response-policy</
code> option, it is now
possible to configure RPZ rewrite logging on a per-zone basis
using the <
code class="option">log</
code> clause.
The default preferred glue is now the address type of the
transport the query was received over.
On machines with 2 or more processors (CPU), the default value
for the number of UDP listeners has been changed to the number
of detected processors minus one.
Zone transfers now use smaller message sizes to improve
message compression. This results in reduced network usage.
Added support for the AVC resource record type (Application
Changed <
span class="command"><
strong>rndc reconfig</
strong></
span> behavior so that newly
added zones are loaded asynchronously and the loading does not
<
div class="titlepage"><
div><
div><
h3 class="title">
<
a name="relnotes_port"></
a>Porting Changes</
h3></
div></
div></
div>
<
div class="itemizedlist"><
ul class="itemizedlist" style="list-style-type: disc; "><
li class="listitem"><
p>
<
div class="titlepage"><
div><
div><
h3 class="title">
<
a name="relnotes_bugs"></
a>Bug Fixes</
h3></
div></
div></
div>
<
div class="itemizedlist"><
ul class="itemizedlist" style="list-style-type: disc; ">
Fixed a crash when calling <
span class="command"><
strong>rndc stats</
strong></
span> on some
Windows builds: some Visual Studio compilers generate code that
crashes when the "%z" printf() format specifier is used. [RT #42380]
Windows installs were failing due to triggering UAC without
the installation binary being signed.
A change in the internal binary representation of the RBT database
node structure enabled a race condition to occur (especially when
BIND was built with certain compilers or optimizer settings),
leading to inconsistent database state which caused random
assertion failures. [RT #42380]
<
div class="titlepage"><
div><
div><
h3 class="title">
<
a name="end_of_life"></
a>End of Life</
h3></
div></
div></
div>
The end of life for BIND 9.11 is yet to be determined but
will not be before BIND 9.13.0 has been released for 6 months.
<
div class="titlepage"><
div><
div><
h3 class="title">
<
a name="relnotes_thanks"></
a>Thank You</
h3></
div></
div></
div>
Thank you to everyone who assisted us in making this release possible.
If you would like to contribute to ISC to assist us in continuing to
make quality open source software, please visit our donations page at