# # Example configuration file. # # See unbound.conf(5) man page, version 1.5.9. # # this is a comment. #Use this to include other text into the file. #include: "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. # statistics-interval: 0 # enable cumulative statistics, without clearing them after printing. # statistics-cumulative: no # enable extended statistics (query types, answer codes, status) # printed from unbound-control. default off, because of speed. # extended-statistics: no # number of threads to create. 1 disables threading. # num-threads: 1 # 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: 192.0.2.153 # interface: 192.0.2.154 # interface: 192.0.2.154@5003 # interface: 2001:DB8::5 # enable this feature to copy the source address of queries to reply. # Socket options are not supported on all platforms. experimental. # 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 # 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. # outgoing-port-permit: 32768 # 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. # outgoing-port-avoid: "3200-3208" # 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. # so-reuseport: no # 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: no # 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 # EDNS reassembly buffer to advertise to UDP peers (the actual buffer # is set with msg-buffer-size). 1480 can solve fragmentation (timeouts). # edns-buffer-size: 4096 # Maximum UDP response size (not applied to TCP response). # Suggested values are 512 to 4096. Default is 4096. 65536 disables it. # max-udp-size: 4096 # 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 # 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 # 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 # Enable IPv4, "yes" or "no". # do-ip4: yes # Enable IPv6, "yes" or "no". # do-ip6: yes # Enable UDP, "yes" or "no". # 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 # 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 # Detach from the terminal, run in background, "yes" or "no". # 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_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 # 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/random (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/unbound" # 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. # directory: "/var/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, with identity "unbound". If yes, it overrides the logfile. # use-syslog: yes # print UTC timestamp in ascii to logfile, default is epoch in seconds. # log-time-ascii: no # print one line with time, IP, name, type, class for every query. # log-queries: no # the pid file. Can be an absolute path outside of chroot/work dir. # pidfile: "/var/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 # the identity to report. Leave "" or default to return hostname. # identity: "" # the version to report. Leave "" or default to return package version. # version: "" # 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: no # 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: no # 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: no # 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 NS when possible. # qname-minimisation: no # 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-whitelist: "licdn.com" # 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: 0 # 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: no # if yes, perform key lookups adjacent to normal lookups. # prefetch-key: no # if yes, Unbound rotates RRSet order in response. # rrset-roundrobin: no # if yes, Unbound doesn't insert authority/additional sections # into response messages when those sections are not required. # minimal-responses: no # 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" # module-config: "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/unbound/root.key" # File with DLV trusted keys. Same format as trust-anchor-file. # There can be only one DLV configured, it is trusted from root down. # DLV is going to be decommissioned. Please do not use it any more. # dlv-anchor-file: "dlv.isc.org.key" # 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: "" # 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 # 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. # 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 # 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: 0 # 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 500 4096 2500" # 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 (used for DLV). # 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: "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. # 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: # local-data: "" # 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 resolves normally, but logs client IP address # o inform_deny drops queries and logs client IP address # # 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" # service clients over SSL (on the TCP sockets), with plain DNS inside # the SSL stream. Give the certificate to use and private key. # default is "" (disabled). requires restart to take effect. # ssl-service-key: "path/to/privatekeyfile.key" # ssl-service-pem: "path/to/publiccertfile.pem" # ssl-port: 853 # request upstream over SSL (with plain DNS inside the SSL stream). # Default is no. Can be turned on and off with unbound-control. # ssl-upstream: 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 # 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: example 1000 # Python config section. To enable: # o use --with-pythonmodule to configure before compiling. # o list python in the module-config string (above) to enable. # o and give a python-script to run. python: # Script file to load # python-script: "/var/unbound/ubmodule-tst.py" # Remote control config section. remote-control: # Enable remote control with unbound-control(8) here. # set up the keys and certificates with unbound-control-setup. # control-enable: no # 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. # control-interface: 127.0.0.1 # control-interface: ::1 # port number for remote control operations. # control-port: 8953 # unbound server key file. # server-key-file: "/var/unbound/unbound_server.key" # unbound server certificate file. # server-cert-file: "/var/unbound/unbound_server.pem" # unbound-control key file. # control-key-file: "/var/unbound/unbound_control.key" # unbound-control certificate file. # control-cert-file: "/var/unbound/unbound_control.pem" # 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-zone: # name: "example.org" # stub-host: ns.example.com. # 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-zone: # name: "example.org" # forward-host: fwd.example.com