#
# Example configuration file.
#
# See unbound.conf(5) man page
#
# this is a comment.
# Use this anywhere in the file to include other text into this file.
#include: "otherfile.conf"
# Use this anywhere in the file to include other text, that explicitly starts a
# clause, into this file. Text after this directive needs to start a clause.
#include-toplevel: "otherfile.conf"
# The server clause sets the main parameters.
server:
# whitespace is not necessary, but looks cleaner.
# verbosity number, 0 is least verbose. 1 is default.
verbosity: 1
# print statistics to the log (for every thread) every N seconds.
# Set to "" or 0 to disable. Default is disabled.
# Needs to be disabled for munin plugin
statistics-interval: 0
# enable shm for stats, default no. if you enable also enable
# statistics-interval, every time it also writes stats to the
# shared memory segment keyed with shm-key.
# shm-enable: no
# shm for stats uses this key, and key+1 for the shared mem segment.
# shm-key: 11777
# enable cumulative statistics, without clearing them after printing.
# Needs to be disabled for munin plugin
statistics-cumulative: no
# enable extended statistics (query types, answer codes, status)
# printed from unbound-control. default off, because of speed.
# Needs to be enabled for munin plugin
extended-statistics: yes
# number of threads to create. 1 disables threading.
num-threads: 4
# specify the interfaces to answer queries from by ip-address.
# The default is to listen to localhost (127.0.0.1 and ::1).
# specify 0.0.0.0 and ::0 to bind to all available interfaces.
# specify every interface[@port] on a new 'interface:' labelled line.
# The listen interfaces are not changed on reload, only on restart.
# interface: 0.0.0.0
# interface: ::0
# interface: 192.0.2.153
# interface: 192.0.2.154
# interface: 192.0.2.154@5003
# interface: 2001:DB8::5
#
# for dns over tls and raw dns over port 80
# interface: 0.0.0.0@443
# interface: ::0@443
# interface: 0.0.0.0@80
# interface: ::0@80
# enable this feature to copy the source address of queries to reply.
# Socket options are not supported on all platforms. experimental.
# interface-automatic: yes
#
# NOTE: Enable this option when specifying interface 0.0.0.0 or ::0
# NOTE: Disabled per Fedora policy not to listen to * on default install
# NOTE: If deploying on non-default port, eg 80/443, this needs to be disabled
interface-automatic: no
# port to answer queries from
# port: 53
# specify the interfaces to send outgoing queries to authoritative
# server from by ip-address. If none, the default (all) interface
# is used. Specify every interface on a 'outgoing-interface:' line.
# outgoing-interface: 192.0.2.153
# outgoing-interface: 2001:DB8::5
# outgoing-interface: 2001:DB8::6
# Specify a netblock to use remainder 64 bits as random bits for
# upstream queries. Uses freebind option (Linux).
# outgoing-interface: 2001:DB8::/64
# Also (Linux:) ip -6 addr add 2001:db8::/64 dev lo
# And: ip -6 route add local 2001:db8::/64 dev lo
# And set prefer-ip6: yes to use the ip6 randomness from a netblock.
# Set this to yes to prefer ipv6 upstream servers over ipv4.
# prefer-ip6: no
# Prefer ipv4 upstream servers, even if ipv6 is available.
# prefer-ip4: no
# number of ports to allocate per thread, determines the size of the
# port range that can be open simultaneously. About double the
# num-queries-per-thread, or, use as many as the OS will allow you.
# outgoing-range: 4096
# permit Unbound to use this port number or port range for
# making outgoing queries, using an outgoing interface.
# Only ephemeral ports are allowed by SElinux
outgoing-port-permit: 32768-60999
# deny Unbound the use this of port number or port range for
# making outgoing queries, using an outgoing interface.
# Use this to make sure Unbound does not grab a UDP port that some
# other server on this computer needs. The default is to avoid
# IANA-assigned port numbers.
# If multiple outgoing-port-permit and outgoing-port-avoid options
# are present, they are processed in order.
# Our SElinux policy does not allow non-ephemeral ports to be used
outgoing-port-avoid: 0-32767
outgoing-port-avoid: 61000-65535
# number of outgoing simultaneous tcp buffers to hold per thread.
# outgoing-num-tcp: 10
# number of incoming simultaneous tcp buffers to hold per thread.
# incoming-num-tcp: 10
# buffer size for UDP port 53 incoming (SO_RCVBUF socket option).
# 0 is system default. Use 4m to catch query spikes for busy servers.
# so-rcvbuf: 0
# buffer size for UDP port 53 outgoing (SO_SNDBUF socket option).
# 0 is system default. Use 4m to handle spikes on very busy servers.
# so-sndbuf: 0
# use SO_REUSEPORT to distribute queries over threads.
# at extreme load it could be better to turn it off to distribute even.
so-reuseport: yes
# use IP_TRANSPARENT so the interface: addresses can be non-local
# and you can config non-existing IPs that are going to work later on
# (uses IP_BINDANY on FreeBSD).
ip-transparent: yes
# use IP_FREEBIND so the interface: addresses can be non-local
# and you can bind to nonexisting IPs and interfaces that are down.
# Linux only. On Linux you also have ip-transparent that is similar.
# ip-freebind: no
# the value of the Differentiated Services Codepoint (DSCP)
# in the differentiated services field (DS) of the outgoing
# IP packets
# ip-dscp: 0
# EDNS reassembly buffer to advertise to UDP peers (the actual buffer
# is set with msg-buffer-size). 1472 can solve fragmentation (timeouts)
# edns-buffer-size: 1232
# Maximum UDP response size (not applied to TCP response).
# Suggested values are 512 to 4096. Default is 4096. 65536 disables it.
# 3072 causes +dnssec any isc.org queries to need TC=1.
# Helps mitigating DDOS
max-udp-size: 3072
# max memory to use for stream(tcp and tls) waiting result buffers.
# stream-wait-size: 4m
# buffer size for handling DNS data. No messages larger than this
# size can be sent or received, by UDP or TCP. In bytes.
# msg-buffer-size: 65552
# the amount of memory to use for the message cache.
# plain value in bytes or you can append k, m or G. default is "4Mb".
# msg-cache-size: 4m
# the number of slabs to use for the message cache.
# the number of slabs must be a power of 2.
# more slabs reduce lock contention, but fragment memory usage.
# msg-cache-slabs: 4
# the number of queries that a thread gets to service.
# num-queries-per-thread: 1024
# if very busy, 50% queries run to completion, 50% get timeout in msec
# jostle-timeout: 200
# msec to wait before close of port on timeout UDP. 0 disables.
# delay-close: 0
# perform connect for UDP sockets to mitigate ICMP side channel.
# udp-connect: yes
# msec for waiting for an unknown server to reply. Increase if you
# are behind a slow satellite link, to eg. 1128.
# unknown-server-time-limit: 376
# the amount of memory to use for the RRset cache.
# plain value in bytes or you can append k, m or G. default is "4Mb".
# rrset-cache-size: 4m
# the number of slabs to use for the RRset cache.
# the number of slabs must be a power of 2.
# more slabs reduce lock contention, but fragment memory usage.
# rrset-cache-slabs: 4
# the time to live (TTL) value lower bound, in seconds. Default 0.
# If more than an hour could easily give trouble due to stale data.
# cache-min-ttl: 0
# the time to live (TTL) value cap for RRsets and messages in the
# cache. Items are not cached for longer. In seconds.
# cache-max-ttl: 86400
# the time to live (TTL) value cap for negative responses in the cache
# cache-max-negative-ttl: 3600
# the time to live (TTL) value for cached roundtrip times, lameness and
# EDNS version information for hosts. In seconds.
# infra-host-ttl: 900
# minimum wait time for responses, increase if uplink is long. In msec.
# infra-cache-min-rtt: 50
# enable to make server probe down hosts more frequently.
# infra-keep-probing: no
# the number of slabs to use for the Infrastructure cache.
# the number of slabs must be a power of 2.
# more slabs reduce lock contention, but fragment memory usage.
# infra-cache-slabs: 4
# the maximum number of hosts that are cached (roundtrip, EDNS, lame).
# infra-cache-numhosts: 10000
# define a number of tags here, use with local-zone, access-control.
# repeat the define-tag statement to add additional tags.
# define-tag: "tag1 tag2 tag3"
# Enable IPv4, "yes" or "no".
# do-ip4: yes
# Enable IPv6, "yes" or "no".
# do-ip6: yes
# Enable UDP, "yes" or "no".
# NOTE: if setting up an Unbound on tls443 for public use, you might want to
# disable UDP to avoid being used in DNS amplification attacks.
# do-udp: yes
# Enable TCP, "yes" or "no".
# do-tcp: yes
# upstream connections use TCP only (and no UDP), "yes" or "no"
# useful for tunneling scenarios, default no.
# tcp-upstream: no
# upstream connections also use UDP (even if do-udp is no).
# useful if if you want UDP upstream, but don't provide UDP downstream.
# udp-upstream-without-downstream: no
# Maximum segment size (MSS) of TCP socket on which the server
# responds to queries. Default is 0, system default MSS.
# tcp-mss: 0
# Maximum segment size (MSS) of TCP socket for outgoing queries.
# Default is 0, system default MSS.
# outgoing-tcp-mss: 0
# Idle TCP timeout, connection closed in milliseconds
# tcp-idle-timeout: 30000
# Enable EDNS TCP keepalive option.
edns-tcp-keepalive: yes
# Timeout for EDNS TCP keepalive, in msec.
# edns-tcp-keepalive-timeout: 120000
# Fedora note: do not activate this - can cause a crash
# Use systemd socket activation for UDP, TCP, and control sockets.
# use-systemd: no
# Detach from the terminal, run in background, "yes" or "no".
# Set the value to "no" when Unbound runs as systemd service.
# do-daemonize: yes
# control which clients are allowed to make (recursive) queries
# to this server. Specify classless netblocks with /size and action.
# By default everything is refused, except for localhost.
# Choose deny (drop message), refuse (polite error reply),
# allow (recursive ok), allow_setrd (recursive ok, rd bit is forced on),
# allow_snoop (recursive and nonrecursive ok)
# deny_non_local (drop queries unless can be answered from local-data)
# refuse_non_local (like deny_non_local but polite error reply).
# access-control: 0.0.0.0/0 refuse
# access-control: 127.0.0.0/8 allow
# access-control: ::0/0 refuse
# access-control: ::1 allow
# access-control: ::ffff:127.0.0.1 allow
# tag access-control with list of tags (in "" with spaces between)
# Clients using this access control element use localzones that
# are tagged with one of these tags.
# access-control-tag: 192.0.2.0/24 "tag2 tag3"
# set action for particular tag for given access control element
# if you have multiple tag values, the tag used to lookup the action
# is the first tag match between access-control-tag and local-zone-tag
# where "first" comes from the order of the define-tag values.
# access-control-tag-action: 192.0.2.0/24 tag3 refuse
# set redirect data for particular tag for access control element
# access-control-tag-data: 192.0.2.0/24 tag2 "A 127.0.0.1"
# Set view for access control element
# access-control-view: 192.0.2.0/24 viewname
# if given, a chroot(2) is done to the given directory.
# i.e. you can chroot to the working directory, for example,
# for extra security, but make sure all files are in that directory.
#
# If chroot is enabled, you should pass the configfile (from the
# commandline) as a full path from the original root. After the
# chroot has been performed the now defunct portion of the config
# file path is removed to be able to reread the config after a reload.
#
# All other file paths (working dir, logfile, roothints, and
# key files) can be specified in several ways:
# o as an absolute path relative to the new root.
# o as a relative path to the working directory.
# o as an absolute path relative to the original root.
# In the last case the path is adjusted to remove the unused portion.
#
# The pid file can be absolute and outside of the chroot, it is
# written just prior to performing the chroot and dropping permissions.
#
# Additionally, Unbound may need to access /dev/urandom (for entropy).
# How to do this is specific to your OS.
#
# If you give "" no chroot is performed. The path must not end in a /.
# chroot: "/var/lib/unbound"
chroot: ""
# if given, user privileges are dropped (after binding port),
# and the given username is assumed. Default is user "unbound".
# If you give "" no privileges are dropped.
username: "unbound"
# the working directory. The relative files in this config are
# relative to this directory. If you give "" the working directory
# is not changed.
# If you give a server: directory: dir before include: file statements
# then those includes can be relative to the working directory.
directory: "/etc/unbound"
# the log file, "" means log to stderr.
# Use of this option sets use-syslog to "no".
# logfile: ""
# Log to syslog(3) if yes. The log facility LOG_DAEMON is used to
# log to. If yes, it overrides the logfile.
# use-syslog: yes
# Log identity to report. if empty, defaults to the name of argv[0]
# (usually "unbound").
# log-identity: ""
# print UTC timestamp in ascii to logfile, default is epoch in seconds.
log-time-ascii: yes
# print one line with time, IP, name, type, class for every query.
# log-queries: no
# print one line per reply, with time, IP, name, type, class, rcode,
# timetoresolve, fromcache and responsesize.
# log-replies: no
# log with tag 'query' and 'reply' instead of 'info' for
# filtering log-queries and log-replies from the log.
# log-tag-queryreply: no
# log the local-zone actions, like local-zone type inform is enabled
# also for the other local zone types.
# log-local-actions: no
# print log lines that say why queries return SERVFAIL to clients.
# log-servfail: no
# the pid file. Can be an absolute path outside of chroot/work dir.
pidfile: "/var/run/unbound/unbound.pid"
# file to read root hints from.
# get one from https://www.internic.net/domain/named.cache
# root-hints: ""
# enable to not answer id.server and hostname.bind queries.
# hide-identity: no
# enable to not answer version.server and version.bind queries.
# hide-version: no
# enable to not set the User-Agent HTTP header.
# hide-http-user-agent: no
# enable to not answer trustanchor.unbound queries.
# hide-trustanchor: no
# enable to not set the User-Agent HTTP header.
# hide-http-user-agent: no
# the identity to report. Leave "" or default to return hostname.
# identity: ""
# the version to report. Leave "" or default to return package version.
# version: ""
# NSID identity (hex string, or "ascii_somestring"). default disabled.
# nsid: "aabbccdd"
# User-Agent HTTP header to use. Leave "" or default to use package name
# and version.
# http-user-agent: ""
# the target fetch policy.
# series of integers describing the policy per dependency depth.
# The number of values in the list determines the maximum dependency
# depth the recursor will pursue before giving up. Each integer means:
# -1 : fetch all targets opportunistically,
# 0: fetch on demand,
# positive value: fetch that many targets opportunistically.
# Enclose the list of numbers between quotes ("").
# target-fetch-policy: "3 2 1 0 0"
# Harden against very small EDNS buffer sizes.
# harden-short-bufsize: yes
# Harden against unseemly large queries.
# harden-large-queries: no
# Harden against out of zone rrsets, to avoid spoofing attempts.
harden-glue: yes
# Harden against receiving dnssec-stripped data. If you turn it
# off, failing to validate dnskey data for a trustanchor will
# trigger insecure mode for that zone (like without a trustanchor).
# Default on, which insists on dnssec data for trust-anchored zones.
harden-dnssec-stripped: yes
# Harden against queries that fall under dnssec-signed nxdomain names.
harden-below-nxdomain: yes
# Harden the referral path by performing additional queries for
# infrastructure data. Validates the replies (if possible).
# Default off, because the lookups burden the server. Experimental
# implementation of draft-wijngaards-dnsext-resolver-side-mitigation.
harden-referral-path: yes
# Harden against algorithm downgrade when multiple algorithms are
# advertised in the DS record. If no, allows the weakest algorithm
# to validate the zone.
# harden-algo-downgrade: no
# Sent minimum amount of information to upstream servers to enhance
# privacy. Only sent minimum required labels of the QNAME and set QTYPE
# to A when possible.
qname-minimisation: yes
# QNAME minimisation in strict mode. Do not fall-back to sending full
# QNAME to potentially broken nameservers. A lot of domains will not be
# resolvable when this option in enabled.
# This option only has effect when qname-minimisation is enabled.
# qname-minimisation-strict: no
# Aggressive NSEC uses the DNSSEC NSEC chain to synthesize NXDOMAIN
# and other denials, using information from previous NXDOMAINs answers.
aggressive-nsec: yes
# Use 0x20-encoded random bits in the query to foil spoof attempts.
# This feature is an experimental implementation of draft dns-0x20.
# use-caps-for-id: no
# Domains (and domains in them) without support for dns-0x20 and
# the fallback fails because they keep sending different answers.
# caps-exempt: "licdn.com"
# caps-exempt: "senderbase.org"
# Enforce privacy of these addresses. Strips them away from answers.
# It may cause DNSSEC validation to additionally mark it as bogus.
# Protects against 'DNS Rebinding' (uses browser as network proxy).
# Only 'private-domain' and 'local-data' names are allowed to have
# these private addresses. No default.
# private-address: 10.0.0.0/8
# private-address: 172.16.0.0/12
# private-address: 192.168.0.0/16
# private-address: 169.254.0.0/16
# private-address: fd00::/8
# private-address: fe80::/10
# private-address: ::ffff:0:0/96
# Allow the domain (and its subdomains) to contain private addresses.
# local-data statements are allowed to contain private addresses too.
# private-domain: "example.com"
# If nonzero, unwanted replies are not only reported in statistics,
# but also a running total is kept per thread. If it reaches the
# threshold, a warning is printed and a defensive action is taken,
# the cache is cleared to flush potential poison out of it.
# A suggested value is 10000000, the default is 0 (turned off).
unwanted-reply-threshold: 10000000
# Do not query the following addresses. No DNS queries are sent there.
# List one address per entry. List classless netblocks with /size,
# do-not-query-address: 127.0.0.1/8
# do-not-query-address: ::1
# if yes, the above default do-not-query-address entries are present.
# if no, localhost can be queried (for testing and debugging).
# do-not-query-localhost: yes
# if yes, perform prefetching of almost expired message cache entries.
prefetch: yes
# if yes, perform key lookups adjacent to normal lookups.
prefetch-key: yes
# deny queries of type ANY with an empty response.
deny-any: yes
# if yes, Unbound rotates RRSet order in response.
rrset-roundrobin: yes
# if yes, Unbound doesn't insert authority/additional sections
# into response messages when those sections are not required.
minimal-responses: yes
# true to disable DNSSEC lameness check in iterator.
# disable-dnssec-lame-check: no
# module configuration of the server. A string with identifiers
# separated by spaces. Syntax: "[dns64] [validator] iterator"
# most modules have to be listed at the beginning of the line,
# except cachedb(just before iterator), and python (at the beginning,
# or, just before the iterator).
module-config: "ipsecmod validator iterator"
# File with trusted keys, kept uptodate using RFC5011 probes,
# initial file like trust-anchor-file, then it stores metadata.
# Use several entries, one per domain name, to track multiple zones.
#
# If you want to perform DNSSEC validation, run unbound-anchor before
# you start Unbound (i.e. in the system boot scripts). And enable:
# Please note usage of unbound-anchor root anchor is at your own risk
# and under the terms of our LICENSE (see that file in the source).
# auto-trust-anchor-file: "/var/lib/unbound/root.key"
# trust anchor signaling sends a RFC8145 key tag query after priming.
trust-anchor-signaling: yes
# Root key trust anchor sentinel (draft-ietf-dnsop-kskroll-sentinel)
root-key-sentinel: yes
# File with trusted keys for validation. Specify more than one file
# with several entries, one file per entry.
# Zone file format, with DS and DNSKEY entries.
# Note this gets out of date, use auto-trust-anchor-file please.
# trust-anchor-file: ""
# Trusted key for validation. DS or DNSKEY. specify the RR on a
# single line, surrounded by "". TTL is ignored. class is IN default.
# Note this gets out of date, use auto-trust-anchor-file please.
# (These examples are from August 2007 and may not be valid anymore).
# trust-anchor: "nlnetlabs.nl. DNSKEY 257 3 5 AQPzzTWMz8qSWIQlfRnPckx2BiVmkVN6LPupO3mbz7FhLSnm26n6iG9N Lby97Ji453aWZY3M5/xJBSOS2vWtco2t8C0+xeO1bc/d6ZTy32DHchpW 6rDH1vp86Ll+ha0tmwyy9QP7y2bVw5zSbFCrefk8qCUBgfHm9bHzMG1U BYtEIQ=="
# trust-anchor: "jelte.nlnetlabs.nl. DS 42860 5 1 14D739EB566D2B1A5E216A0BA4D17FA9B038BE4A"
# File with trusted keys for validation. Specify more than one file
# with several entries, one file per entry. Like trust-anchor-file
# but has a different file format. Format is BIND-9 style format,
# the trusted-keys { name flag proto algo "key"; }; clauses are read.
# you need external update procedures to track changes in keys.
# trusted-keys-file: ""
#
trusted-keys-file: /etc/unbound/keys.d/*.key
auto-trust-anchor-file: "/var/lib/unbound/root.key"
# Ignore chain of trust. Domain is treated as insecure.
# domain-insecure: "example.com"
# Override the date for validation with a specific fixed date.
# Do not set this unless you are debugging signature inception
# and expiration. "" or "0" turns the feature off. -1 ignores date.
# val-override-date: ""
# The time to live for bogus data, rrsets and messages. This avoids
# some of the revalidation, until the time interval expires. in secs.
# val-bogus-ttl: 60
# The signature inception and expiration dates are allowed to be off
# by 10% of the signature lifetime (expir-incep) from our local clock.
# This leeway is capped with a minimum and a maximum. In seconds.
# val-sig-skew-min: 3600
# val-sig-skew-max: 86400
# The maximum number the validator should restart validation with
# another authority in case of failed validation.
# val-max-restart: 5
# Should additional section of secure message also be kept clean of
# unsecure data. Useful to shield the users of this validator from
# potential bogus data in the additional section. All unsigned data
# in the additional section is removed from secure messages.
val-clean-additional: yes
# Turn permissive mode on to permit bogus messages. Thus, messages
# for which security checks failed will be returned to clients,
# instead of SERVFAIL. It still performs the security checks, which
# result in interesting log files and possibly the AD bit in
# replies if the message is found secure. The default is off.
# NOTE: TURNING THIS ON DISABLES ALL DNSSEC SECURITY
val-permissive-mode: no
# Ignore the CD flag in incoming queries and refuse them bogus data.
# Enable it if the only clients of Unbound are legacy servers (w2008)
# that set CD but cannot validate themselves.
# ignore-cd-flag: no
# Serve expired responses from cache, with serve-expired-reply-ttl in
# the response, and then attempt to fetch the data afresh.
serve-expired: yes
#
# Limit serving of expired responses to configured seconds after
# expiration. 0 disables the limit.
serve-expired-ttl: 14400
#
# Set the TTL of expired records to the serve-expired-ttl value after a
# failed attempt to retrieve the record from upstream. This makes sure
# that the expired records will be served as long as there are queries
# for it.
# serve-expired-ttl-reset: no
#
# TTL value to use when replying with expired data.
# serve-expired-reply-ttl: 30
#
# Time in milliseconds before replying to the client with expired data.
# This essentially enables the serve-stale behavior as specified in
# RFC 8767 that first tries to resolve before
# immediately responding with expired data. 0 disables this behavior.
# A recommended value is 1800.
# serve-expired-client-timeout: 0
# Return the original TTL as received from the upstream name server rather
# than the decrementing TTL as stored in the cache. Enabling this feature
# does not impact cache expiry, it only changes the TTL Unbound embeds in
# responses to queries. Note that enabling this feature implicitly disables
# enforcement of the configured minimum and maximum TTL.
# serve-original-ttl: no
# Have the validator log failed validations for your diagnosis.
# 0: off. 1: A line per failed user query. 2: With reason and bad IP.
val-log-level: 1
# It is possible to configure NSEC3 maximum iteration counts per
# keysize. Keep this table very short, as linear search is done.
# A message with an NSEC3 with larger count is marked insecure.
# List in ascending order the keysize and count values.
# val-nsec3-keysize-iterations: "1024 150 2048 150 4096 150"
# if enabled, ZONEMD verification failures do not block the zone.
# zonemd-permissive-mode: no
# instruct the auto-trust-anchor-file probing to add anchors after ttl.
# add-holddown: 2592000 # 30 days
# instruct the auto-trust-anchor-file probing to del anchors after ttl.
# del-holddown: 2592000 # 30 days
# auto-trust-anchor-file probing removes missing anchors after ttl.
# If the value 0 is given, missing anchors are not removed.
# keep-missing: 31622400 # 366 days
# debug option that allows very small holddown times for key rollover,
# otherwise the RFC mandates probe intervals must be at least 1 hour.
# permit-small-holddown: no
# the amount of memory to use for the key cache.
# plain value in bytes or you can append k, m or G. default is "4Mb".
# key-cache-size: 4m
# the number of slabs to use for the key cache.
# the number of slabs must be a power of 2.
# more slabs reduce lock contention, but fragment memory usage.
# key-cache-slabs: 4
# the amount of memory to use for the negative cache.
# plain value in bytes or you can append k, m or G. default is "1Mb".
# neg-cache-size: 1m
# By default, for a number of zones a small default 'nothing here'
# reply is built-in. Query traffic is thus blocked. If you
# wish to serve such zone you can unblock them by uncommenting one
# of the nodefault statements below.
# You may also have to use domain-insecure: zone to make DNSSEC work,
# unless you have your own trust anchors for this zone.
# local-zone: "localhost." nodefault
# local-zone: "127.in-addr.arpa." nodefault
# local-zone: "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa." nodefault
# local-zone: "onion." nodefault
# local-zone: "test." nodefault
# local-zone: "invalid." nodefault
# local-zone: "10.in-addr.arpa." nodefault
# local-zone: "16.172.in-addr.arpa." nodefault
# local-zone: "17.172.in-addr.arpa." nodefault
# local-zone: "18.172.in-addr.arpa." nodefault
# local-zone: "19.172.in-addr.arpa." nodefault
# local-zone: "20.172.in-addr.arpa." nodefault
# local-zone: "21.172.in-addr.arpa." nodefault
# local-zone: "22.172.in-addr.arpa." nodefault
# local-zone: "23.172.in-addr.arpa." nodefault
# local-zone: "24.172.in-addr.arpa." nodefault
# local-zone: "25.172.in-addr.arpa." nodefault
# local-zone: "26.172.in-addr.arpa." nodefault
# local-zone: "27.172.in-addr.arpa." nodefault
# local-zone: "28.172.in-addr.arpa." nodefault
# local-zone: "29.172.in-addr.arpa." nodefault
# local-zone: "30.172.in-addr.arpa." nodefault
# local-zone: "31.172.in-addr.arpa." nodefault
# local-zone: "168.192.in-addr.arpa." nodefault
# local-zone: "0.in-addr.arpa." nodefault
# local-zone: "254.169.in-addr.arpa." nodefault
# local-zone: "2.0.192.in-addr.arpa." nodefault
# local-zone: "100.51.198.in-addr.arpa." nodefault
# local-zone: "113.0.203.in-addr.arpa." nodefault
# local-zone: "255.255.255.255.in-addr.arpa." nodefault
# local-zone: "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa." nodefault
# local-zone: "d.f.ip6.arpa." nodefault
# local-zone: "8.e.f.ip6.arpa." nodefault
# local-zone: "9.e.f.ip6.arpa." nodefault
# local-zone: "a.e.f.ip6.arpa." nodefault
# local-zone: "b.e.f.ip6.arpa." nodefault
# local-zone: "8.b.d.0.1.0.0.2.ip6.arpa." nodefault
# And for 64.100.in-addr.arpa. to 127.100.in-addr.arpa.
# Add example.com into ipset
# local-zone: "example.com" ipset
# If Unbound is running service for the local host then it is useful
# to perform lan-wide lookups to the upstream, and unblock the
# long list of local-zones above. If this Unbound is a dns server
# for a network of computers, disabled is better and stops information
# leakage of local lan information.
# unblock-lan-zones: no
# The insecure-lan-zones option disables validation for
# these zones, as if they were all listed as domain-insecure.
# insecure-lan-zones: no
# a number of locally served zones can be configured.
# local-zone: <zone> <type>
# local-data: "<resource record string>"
# o deny serves local data (if any), else, drops queries.
# o refuse serves local data (if any), else, replies with error.
# o static serves local data, else, nxdomain or nodata answer.
# o transparent gives local data, but resolves normally for other names
# o redirect serves the zone data for any subdomain in the zone.
# o nodefault can be used to normally resolve AS112 zones.
# o typetransparent resolves normally for other types and other names
# o inform acts like transparent, but logs client IP address
# o inform_deny drops queries and logs client IP address
# o inform_redirect redirects queries and logs client IP address
# o always_transparent, always_refuse, always_nxdomain, always_nodata,
# always_deny resolve in that way but ignore local data for
# that name
# o always_null returns 0.0.0.0 or ::0 for any name in the zone.
# o noview breaks out of that view towards global local-zones.
#
# defaults are localhost address, reverse for 127.0.0.1 and ::1
# and nxdomain for AS112 zones. If you configure one of these zones
# the default content is omitted, or you can omit it with 'nodefault'.
#
# If you configure local-data without specifying local-zone, by
# default a transparent local-zone is created for the data.
#
# You can add locally served data with
# local-zone: "local." static
# local-data: "mycomputer.local. IN A 192.0.2.51"
# local-data: 'mytext.local TXT "content of text record"'
#
# You can override certain queries with
# local-data: "adserver.example.com A 127.0.0.1"
#
# You can redirect a domain to a fixed address with
# (this makes example.com, www.example.com, etc, all go to 192.0.2.3)
# local-zone: "example.com" redirect
# local-data: "example.com A 192.0.2.3"
#
# Shorthand to make PTR records, "IPv4 name" or "IPv6 name".
# You can also add PTR records using local-data directly, but then
# you need to do the reverse notation yourself.
# local-data-ptr: "192.0.2.3 www.example.com"
include: /etc/unbound/local.d/*.conf
# tag a localzone with a list of tag names (in "" with spaces between)
# local-zone-tag: "example.com" "tag2 tag3"
# add a netblock specific override to a localzone, with zone type
# local-zone-override: "example.com" 192.0.2.0/24 refuse
# service clients over TLS (on the TCP sockets) with plain DNS inside
# the TLS stream, and over HTTPS using HTTP/2 as specified in RFC8484.
# Give the certificate to use and private key.
# default is "" (disabled). requires restart to take effect.
# tls-service-key: "/etc/unbound/unbound_server.key"
# tls-service-pem: "/etc/unbound/unbound_server.pem"
# tls-port: 853
# https-port: 443
# cipher setting for TLSv1.2
# tls-ciphers: "DHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-SHA256:DHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA256"
# cipher setting for TLSv1.3
# tls-ciphersuites: "TLS_AES_128_GCM_SHA256:TLS_AES_128_CCM_8_SHA256:TLS_AES_128_CCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256"
# Fedora/RHEL: use system-wide crypto policies
tls-ciphers: "PROFILE=SYSTEM"
# TODO: ask system-wide crypto people what to use here
#tls-ciphersuites: "PROFILE=SYSTEM" # does not work
# Pad responses to padded queries received over TLS
# pad-responses: yes
# Padded responses will be padded to the closest multiple of this size.
# pad-responses-block-size: 468
# Use the SNI extension for TLS connections. Default is yes.
# Changing the value requires a reload.
# tls-use-sni: yes
# Add the secret file for TLS Session Ticket.
# Secret file must be 80 bytes of random data.
# First key use to encrypt and decrypt TLS session tickets.
# Other keys use to decrypt only.
# requires restart to take effect.
# tls-session-ticket-keys: "path/to/secret_file1"
# tls-session-ticket-keys: "path/to/secret_file2"
# request upstream over TLS (with plain DNS inside the TLS stream).
# Default is no. Can be turned on and off with unbound-control.
# tls-upstream: no
# Certificates used to authenticate connections made upstream.
# tls-cert-bundle: ""
# Add system certs to the cert bundle, from the Windows Cert Store
# tls-win-cert: no
# Pad queries over TLS upstreams
# pad-queries: yes
# Padded queries will be padded to the closest multiple of this size.
# pad-queries-block-size: 128
# Also serve tls on these port numbers (eg. 443, ...), by listing
# tls-additional-port: portno for each of the port numbers.
# HTTP endpoint to provide DNS-over-HTTPS service on.
# http-endpoint: "/dns-query"
# HTTP/2 SETTINGS_MAX_CONCURRENT_STREAMS value to use.
# http-max-streams: 100
# Maximum number of bytes used for all HTTP/2 query buffers.
# http-query-buffer-size: 4m
# Maximum number of bytes used for all HTTP/2 response buffers.
# http-response-buffer-size: 4m
# Set TCP_NODELAY socket option on sockets used for DNS-over-HTTPS
# service.
# http-nodelay: yes
# Disable TLS for DNS-over-HTTP downstream service.
# http-notls-downstream: no
# DNS64 prefix. Must be specified when DNS64 is use.
# Enable dns64 in module-config. Used to synthesize IPv6 from IPv4.
# dns64-prefix: 64:ff9b::0/96
# DNS64 ignore AAAA records for these domains and use A instead.
# dns64-ignore-aaaa: "example.com"
# ratelimit for uncached, new queries, this limits recursion effort.
# ratelimiting is experimental, and may help against randomqueryflood.
# if 0(default) it is disabled, otherwise state qps allowed per zone.
# ratelimit: 0
# ratelimits are tracked in a cache, size in bytes of cache (or k,m).
# ratelimit-size: 4m
# ratelimit cache slabs, reduces lock contention if equal to cpucount.
# ratelimit-slabs: 4
# 0 blocks when ratelimited, otherwise let 1/xth traffic through
# ratelimit-factor: 10
# override the ratelimit for a specific domain name.
# give this setting multiple times to have multiple overrides.
# ratelimit-for-domain: example.com 1000
# override the ratelimits for all domains below a domain name
# can give this multiple times, the name closest to the zone is used.
# ratelimit-below-domain: com 1000
# global query ratelimit for all ip addresses.
# feature is experimental.
# if 0(default) it is disabled, otherwise states qps allowed per ip address
# ip-ratelimit: 0
# ip ratelimits are tracked in a cache, size in bytes of cache (or k,m).
# ip-ratelimit-size: 4m
# ip ratelimit cache slabs, reduces lock contention if equal to cpucount.
# ip-ratelimit-slabs: 4
# 0 blocks when ip is ratelimited, otherwise let 1/xth traffic through
# ip-ratelimit-factor: 10
# Limit the number of connections simultaneous from a netblock
# tcp-connection-limit: 192.0.2.0/24 12
# select from the fastest servers this many times out of 1000. 0 means
# the fast server select is disabled. prefetches are not sped up.
# fast-server-permil: 0
# the number of servers that will be used in the fast server selection.
# fast-server-num: 3
# Specific options for ipsecmod. Unbound needs to be configured with
# --enable-ipsecmod for these to take effect.
#
# Enable or disable ipsecmod (it still needs to be defined in
# module-config above). Can be used when ipsecmod needs to be
# enabled/disabled via remote-control(below).
# Fedora: module will be enabled on-demand by libreswan
ipsecmod-enabled: no
# Path to executable external hook. It must be defined when ipsecmod is
# listed in module-config (above).
# ipsecmod-hook: "./my_executable"
ipsecmod-hook:/usr/libexec/ipsec/_unbound-hook
# When enabled Unbound will reply with SERVFAIL if the return value of
# the ipsecmod-hook is not 0.
# ipsecmod-strict: no
#
# Maximum time to live (TTL) for cached A/AAAA records with IPSECKEY.
# ipsecmod-max-ttl: 3600
#
# Reply with A/AAAA even if the relevant IPSECKEY is bogus. Mainly used for
# testing.
# ipsecmod-ignore-bogus: no
#
# Domains for which ipsecmod will be triggered. If not defined (default)
# all domains are treated as being allowed.
# ipsecmod-allow: "example.com"
# ipsecmod-allow: "nlnetlabs.nl"
# Timeout for REUSE entries in milliseconds.
# tcp-reuse-timeout: 60000
# Max number of queries on a reuse connection.
# max-reuse-tcp-queries: 200
# Timeout in milliseconds for TCP queries to auth servers.
# tcp-auth-query-timeout: 3000
# Python config section. To enable:
# o use --with-pythonmodule to configure before compiling.
# o list python in the module-config string (above) to enable.
# It can be at the start, it gets validated results, or just before
# the iterator and process before DNSSEC validation.
# o and give a python-script to run.
python:
# Script file to load
# python-script: "/etc/unbound/ubmodule-tst.py"
# Dynamic library config section. To enable:
# o use --with-dynlibmodule to configure before compiling.
# o list dynlib in the module-config string (above) to enable.
# It can be placed anywhere, the dynlib module is only a very thin wrapper
# to load modules dynamically.
# o and give a dynlib-file to run. If more than one dynlib entry is listed in
# the module-config then you need one dynlib-file per instance.
dynlib:
# Script file to load
# dynlib-file: "/etc/unbound/dynlib.so"
# Remote control config section.
remote-control:
# Enable remote control with unbound-control(8) here.
# set up the keys and certificates with unbound-control-setup.
# Note: required for unbound-munin package
control-enable: yes
# Set to no and use an absolute path as control-interface to use
# a unix local named pipe for unbound-control.
# control-use-cert: yes
# what interfaces are listened to for remote control.
# give 0.0.0.0 and ::0 to listen to all interfaces.
# set to an absolute path to use a unix local name pipe, certificates
# are not used for that, so key and cert files need not be present.
# control-interface: 127.0.0.1
# control-interface: ::1
# port number for remote control operations.
# control-port: 8953
# for localhost, you can disable use of TLS by setting this to "no"
# For local sockets this option is ignored, and TLS is not used.
control-use-cert: "no"
# Unbound server key file.
server-key-file: "/etc/unbound/unbound_server.key"
# Unbound server certificate file.
server-cert-file: "/etc/unbound/unbound_server.pem"
# unbound-control key file.
control-key-file: "/etc/unbound/unbound_control.key"
# unbound-control certificate file.
control-cert-file: "/etc/unbound/unbound_control.pem"
# Stub and Forward zones
include: /etc/unbound/conf.d/*.conf
# Stub zones.
# Create entries like below, to make all queries for 'example.com' and
# 'example.org' go to the given list of nameservers. list zero or more
# nameservers by hostname or by ipaddress. If you set stub-prime to yes,
# the list is treated as priming hints (default is no).
# With stub-first yes, it attempts without the stub if it fails.
# Consider adding domain-insecure: name and local-zone: name nodefault
# to the server: section if the stub is a locally served zone.
# stub-zone:
# name: "example.com"
# stub-addr: 192.0.2.68
# stub-prime: no
# stub-first: no
# stub-tls-upstream: no
# stub-no-cache: no
# stub-zone:
# name: "example.org"
# stub-host: ns.example.com.
# You can now also dynamically create and delete stub-zone's using
# unbound-control stub_add domain.com 1.2.3.4 5.6.7.8
# unbound-control stub_remove domain.com 1.2.3.4 5.6.7.8
# Forward zones
# Create entries like below, to make all queries for 'example.com' and
# 'example.org' go to the given list of servers. These servers have to handle
# recursion to other nameservers. List zero or more nameservers by hostname
# or by ipaddress. Use an entry with name "." to forward all queries.
# If you enable forward-first, it attempts without the forward if it fails.
# forward-zone:
# name: "example.com"
# forward-addr: 192.0.2.68
# forward-addr: 192.0.2.73@5355 # forward to port 5355.
# forward-first: no
# forward-tls-upstream: no
# forward-no-cache: no
# forward-zone:
# name: "example.org"
# forward-host: fwd.example.com
#
# You can now also dynamically create and delete forward-zone's using
# unbound-control forward_add domain.com 1.2.3.4 5.6.7.8
# unbound-control forward_remove domain.com 1.2.3.4 5.6.7.8
# Authority zones
# The data for these zones is kept locally, from a file or downloaded.
# The data can be served to downstream clients, or used instead of the
# upstream (which saves a lookup to the upstream). The first example
# has a copy of the root for local usage. The second serves example.org
# authoritatively. zonefile: reads from file (and writes to it if you also
# download it), master: fetches with AXFR and IXFR, or url to zonefile.
# With allow-notify: you can give additional (apart from masters) sources of
# notifies.
auth-zone:
name: "."
primary: 199.9.14.201 # b.root-servers.net
primary: 192.33.4.12 # c.root-servers.net
primary: 199.7.91.13 # d.root-servers.net
primary: 192.5.5.241 # f.root-servers.net
primary: 192.112.36.4 # g.root-servers.net
primary: 193.0.14.129 # k.root-servers.net
primary: 192.0.47.132 # xfr.cjr.dns.icann.org
primary: 192.0.32.132 # xfr.lax.dns.icann.org
primary: 2001:500:200::b # b.root-servers.net
primary: 2001:500:2::c # c.root-servers.net
primary: 2001:500:2d::d # d.root-servers.net
primary: 2001:500:2f::f # f.root-servers.net
primary: 2001:500:12::d0d # g.root-servers.net
primary: 2001:7fd::1 # k.root-servers.net
primary: 2620:0:2830:202::132 # xfr.cjr.dns.icann.org
primary: 2620:0:2d0:202::132 # xfr.lax.dns.icann.org
fallback-enabled: yes
for-downstream: no
for-upstream: yes
# auth-zone:
# name: "example.org"
# for-downstream: yes
# for-upstream: yes
# zonemd-check: no
# zonemd-reject-absence: no
# zonefile: "example.org.zone"
# Views
# Create named views. Name must be unique. Map views to requests using
# the access-control-view option. Views can contain zero or more local-zone
# and local-data options. Options from matching views will override global
# options. Global options will be used if no matching view is found.
# With view-first yes, it will try to answer using the global local-zone and
# local-data elements if there is no view specific match.
# view:
# name: "viewname"
# local-zone: "example.com" redirect
# local-data: "example.com A 192.0.2.3"
# local-data-ptr: "192.0.2.3 www.example.com"
# view-first: no
# view:
# name: "anotherview"
# local-zone: "example.com" refuse
# Fedora: DNSCrypt support not enabled since it requires linking to
# another crypto library
#
# DNSCrypt
# Caveats:
# 1. the keys/certs cannot be produced by Unbound. You can use dnscrypt-wrapper
# for this: https://github.com/cofyc/dnscrypt-wrapper/blob/master/README.md#usage
# 2. dnscrypt channel attaches to an interface. you MUST set interfaces to
# listen on `dnscrypt-port` with the follo0wing snippet:
# server:
# interface: 0.0.0.0@443
# interface: ::0@443
#
# Finally, `dnscrypt` config has its own section.
# dnscrypt:
# dnscrypt-enable: yes
# dnscrypt-port: 443
# dnscrypt-provider: 2.dnscrypt-cert.example.com.
# dnscrypt-secret-key: /path/unbound-conf/keys1/1.key
# dnscrypt-secret-key: /path/unbound-conf/keys2/1.key
# dnscrypt-provider-cert: /path/unbound-conf/keys1/1.cert
# dnscrypt-provider-cert: /path/unbound-conf/keys2/1.cert
# CacheDB
# Enable external backend DB as auxiliary cache. Specify the backend name
# (default is "testframe", which has no use other than for debugging and
# testing) and backend-specific options. The 'cachedb' module must be
# included in module-config, just before the iterator module.
# cachedb:
# backend: "testframe"
# # secret seed string to calculate hashed keys
# secret-seed: "default"
#
# # For "redis" backend:
# # redis server's IP address or host name
# redis-server-host: 127.0.0.1
# # redis server's TCP port
# redis-server-port: 6379
# # timeout (in ms) for communication with the redis server
# redis-timeout: 100
# # set timeout on redis records based on DNS response TTL
# redis-expire-records: no
# IPSet
# Add specify domain into set via ipset.
# Note: To enable ipset Unbound needs to run as root user.
# ipset:
# # set name for ip v4 addresses
# name-v4: "list-v4"
# # set name for ip v6 addresses
# name-v6: "list-v6"
#
# Dnstap logging support, if compiled in. To enable, set the dnstap-enable
# to yes and also some of dnstap-log-..-messages to yes. And select an
# upstream log destination, by socket path, TCP or TLS destination.
# dnstap:
# dnstap-enable: no
# # if set to yes frame streams will be used in bidirectional mode
# dnstap-bidirectional: yes
# dnstap-socket-path: "/etc/unbound/dnstap.sock"
# # if "" use the unix socket in dnstap-socket-path, otherwise,
# # set it to "IPaddress[@port]" of the destination.
# dnstap-ip: ""
# # if set to yes if you want to use TLS to dnstap-ip, no for TCP.
# dnstap-tls: yes
# # name for authenticating the upstream server. or "" disabled.
# dnstap-tls-server-name: ""
# # if "", it uses the cert bundle from the main Unbound config.
# dnstap-tls-cert-bundle: ""
# # key file for client authentication, or "" disabled.
# dnstap-tls-client-key-file: ""
# # cert file for client authentication, or "" disabled.
# dnstap-tls-client-cert-file: ""
# dnstap-send-identity: no
# dnstap-send-version: no
# # if "" it uses the hostname.
# dnstap-identity: ""
# # if "" it uses the package version.
# dnstap-version: ""
# dnstap-log-resolver-query-messages: no
# dnstap-log-resolver-response-messages: no
# dnstap-log-client-query-messages: no
# dnstap-log-client-response-messages: no
# dnstap-log-forwarder-query-messages: no
# dnstap-log-forwarder-response-messages: no
# Response Policy Zones
# RPZ policies. Applied in order of configuration. QNAME, Response IP
# Address, nsdname, nsip and clientip triggers are supported. Supported
# actions are: NXDOMAIN, NODATA, PASSTHRU, DROP, Local Data, tcp-only
# and drop. Policies can be loaded from a file, or using zone
# transfer, or using HTTP. The respip module needs to be added
# to the module-config, e.g.: module-config: "respip validator iterator".
# rpz:
# name: "rpz.example.com"
# zonefile: "rpz.example.com"
# primary: 192.0.2.0
# allow-notify: 192.0.2.0/32
# url: http://www.example.com/rpz.example.org.zone
# rpz-action-override: cname
# rpz-cname-override: www.example.org
# rpz-log: yes
# rpz-log-name: "example policy"
# rpz-signal-nxdomain-ra: no
# for-downstream: no
# tags: "example"