Provided by: systemd-resolved_256.5-2ubuntu3.1_amd64 bug

NAME

       resolvectl, resolvconf - Resolve domain names, IPV4 and IPv6 addresses, DNS resource
       records, and services; introspect and reconfigure the DNS resolver

SYNOPSIS

       resolvectl [OPTIONS...] {COMMAND} [NAME...]

DESCRIPTION

       resolvectl may be used to resolve domain names, IPv4 and IPv6 addresses, DNS resource
       records and services with the systemd-resolved.service(8) resolver service. By default,
       the specified list of parameters will be resolved as hostnames, retrieving their IPv4 and
       IPv6 addresses. If the parameters specified are formatted as IPv4 or IPv6 addresses the
       reverse operation is done, and a hostname is retrieved for the specified addresses.

       The program's output contains information about the protocol used for the look-up and on
       which network interface the data was discovered. It also contains information on whether
       the information could be authenticated. All data for which local DNSSEC validation
       succeeds is considered authenticated. Moreover all data originating from local, trusted
       sources is also reported authenticated, including resolution of the local host name, the
       "localhost" hostname or all data from /etc/hosts.

COMMANDS

       query HOSTNAME|ADDRESS...
           Resolve domain names, as well as IPv4 and IPv6 addresses. When used in conjunction
           with --type= or --class= (see below), resolves low-level DNS resource records.

           If a single-label domain name is specified it is searched for according to the
           configured search domains — unless --search=no or --type=/--class= are specified, both
           of which turn this logic off.

           If an international domain name is specified, it is automatically translated according
           to IDNA rules when resolved via classic DNS — but not for look-ups via MulticastDNS or
           LLMNR. If --type=/--class= is used IDNA translation is turned off and domain names are
           processed as specified.

           If combined with --json= (only supported in combination with --type=) will output the
           resource record data in a JSON object.

           Added in version 239.

       service [[NAME] TYPE] DOMAIN
           Resolve RFC 6763 DNS-SD[1] and RFC 2782 SRV[2] services, depending on the specified
           list of parameters. If three parameters are passed the first is assumed to be the
           DNS-SD service name, the second the SRV service type, and the third the domain to
           search in. In this case a full DNS-SD style SRV and TXT lookup is executed. If only
           two parameters are specified, the first is assumed to be the SRV service type, and the
           second the domain to look in. In this case no TXT resource record is requested.
           Finally, if only one parameter is specified, it is assumed to be a domain name, that
           is already prefixed with an SRV type, and an SRV lookup is done (no TXT).

           Added in version 239.

       openpgp EMAIL@DOMAIN...
           Query PGP keys stored as OPENPGPKEY resource records, see RFC 7929[3]. Specified
           e-mail addresses are converted to the corresponding DNS domain name, and any
           OPENPGPKEY keys are printed.

           Added in version 239.

       tlsa [FAMILY] DOMAIN[:PORT]...
           Query TLS public keys stored as TLSA resource records, see RFC 6698[4]. A query will
           be performed for each of the specified names prefixed with the port and family
           ("_port._family.domain"). The port number may be specified after a colon (":"),
           otherwise 443 will be used by default. The family may be specified as the first
           argument, otherwise tcp will be used.

           Added in version 239.

       status [LINK...]
           Shows the global and per-link DNS settings currently in effect. If no command is
           specified, this is the implied default.

           Added in version 239.

       statistics
           Shows general resolver statistics, including information whether DNSSEC is enabled and
           available, as well as resolution and validation statistics.

           Added in version 239.

       reset-statistics
           Resets the statistics counters shown in statistics to zero. This operation requires
           root privileges.

           Added in version 239.

       flush-caches
           Flushes all DNS resource record caches the service maintains locally. This is mostly
           equivalent to sending the SIGUSR2 to the systemd-resolved service.

           Added in version 239.

       reset-server-features
           Flushes all feature level information the resolver learnt about specific servers, and
           ensures that the server feature probing logic is started from the beginning with the
           next look-up request. This is mostly equivalent to sending the SIGRTMIN+1 to the
           systemd-resolved service.

           Added in version 239.

       dns [LINK [SERVER...]], domain [LINK [DOMAIN...]], default-route [LINK [BOOL...]], llmnr
       [LINK [MODE]], mdns [LINK [MODE]], dnssec [LINK [MODE]], dnsovertls [LINK [MODE]], nta
       [LINK [DOMAIN...]]
           Get/set per-interface DNS configuration. These commands may be used to configure
           various DNS settings for network interfaces. These commands may be used to inform
           systemd-resolved or systemd-networkd about per-interface DNS configuration determined
           through external means. The dns command expects IPv4 or IPv6 address specifications of
           DNS servers to use. Each address can optionally take a port number separated with ":",
           a network interface name or index separated with "%", and a Server Name Indication
           (SNI) separated with "#". When IPv6 address is specified with a port number, then the
           address must be in the square brackets. That is, the acceptable full formats are
           "111.222.333.444:9953%ifname#example.com" for IPv4 and
           "[1111:2222::3333]:9953%ifname#example.com" for IPv6. The domain command expects valid
           DNS domains, possibly prefixed with "~", and configures a per-interface search or
           route-only domain. The default-route command expects a boolean parameter, and
           configures whether the link may be used as default route for DNS lookups, i.e. if it
           is suitable for lookups on domains no other link explicitly is configured for. The
           llmnr, mdns, dnssec and dnsovertls commands may be used to configure the per-interface
           LLMNR, MulticastDNS, DNSSEC and DNSOverTLS settings. Finally, nta command may be used
           to configure additional per-interface DNSSEC NTA domains.

           Commands dns, domain and nta can take a single empty string argument to clear their
           respective value lists.

           For details about these settings, their possible values and their effect, see the
           corresponding settings in systemd.network(5).

           Added in version 239.

       revert LINK
           Revert the per-interface DNS configuration. If the DNS configuration is reverted all
           per-interface DNS setting are reset to their defaults, undoing all effects of dns,
           domain, default-route, llmnr, mdns, dnssec, dnsovertls, nta. Note that when a network
           interface disappears all configuration is lost automatically, an explicit reverting is
           not necessary in that case.

           Added in version 239.

       monitor
           Show a continuous stream of local client resolution queries and their responses.
           Whenever a local query is completed the query's DNS resource lookup key and resource
           records are shown. Note that this displays queries issued locally only, and does not
           immediately relate to DNS requests submitted to configured DNS servers or the LLMNR or
           MulticastDNS zones, as lookups may be answered from the local cache, or might result
           in multiple DNS transactions (for example to validate DNSSEC information). If
           CNAME/CNAME redirection chains are followed, a separate query will be displayed for
           each element of the chain. Use --json= to enable JSON output.

           Added in version 252.

       show-cache
           Show current cache content, per scope. Use --json= to enable JSON output.

           Added in version 254.

       show-server-state
           Show detailed server state information, per DNS Server. Use --json= to enable JSON
           output.

           Added in version 255.

       log-level [LEVEL]
           If no argument is given, print the current log level of the manager. If an optional
           argument LEVEL is provided, then the command changes the current log level of the
           manager to LEVEL (accepts the same values as --log-level= described in systemd(1)).

           Added in version 244.

OPTIONS

       -4, -6
           By default, when resolving a hostname, both IPv4 and IPv6 addresses are acquired. By
           specifying -4 only IPv4 addresses are requested, by specifying -6 only IPv6 addresses
           are requested.

           Added in version 239.

       -i INTERFACE, --interface=INTERFACE
           Specifies the network interface to execute the query on. This may either be specified
           as numeric interface index or as network interface string (e.g.  "en0"). Note that
           this option has no effect if system-wide DNS configuration (as configured in
           /etc/resolv.conf or /etc/systemd/resolved.conf) in place of per-link configuration is
           used.

           Added in version 239.

       -p PROTOCOL, --protocol=PROTOCOL
           Specifies the network protocol for the query. May be one of "dns" (i.e. classic
           unicast DNS), "llmnr" (Link-Local Multicast Name Resolution[5]), "llmnr-ipv4",
           "llmnr-ipv6" (LLMNR via the indicated underlying IP protocols), "mdns" (Multicast
           DNS[6]), "mdns-ipv4", "mdns-ipv6" (MDNS via the indicated underlying IP protocols). By
           default the lookup is done via all protocols suitable for the lookup. If used, limits
           the set of protocols that may be used. Use this option multiple times to enable
           resolving via multiple protocols at the same time. The setting "llmnr" is identical to
           specifying this switch once with "llmnr-ipv4" and once via "llmnr-ipv6". Note that
           this option does not force the service to resolve the operation with the specified
           protocol, as that might require a suitable network interface and configuration. The
           special value "help" may be used to list known values.

           Added in version 239.

       -t TYPE, --type=TYPE, -c CLASS, --class=CLASS
           When used in conjunction with the query command, specifies the DNS resource record
           type (e.g.  A, AAAA, MX, ...) and class (e.g.  IN, ANY, ...) to look up. If these
           options are used a DNS resource record set matching the specified class and type is
           requested. The class defaults to IN if only a type is specified. The special value
           "help" may be used to list known values.

           Without these options resolvectl query provides high-level domain name to address and
           address to domain name resolution. With these options it provides low-level DNS
           resource record resolution. The search domain logic is automatically turned off when
           these options are used, i.e. specified domain names need to be fully qualified domain
           names. Moreover, IDNA internal domain name translation is turned off as well, i.e.
           international domain names should be specified in "xn--..."  notation, unless look-up
           in MulticastDNS/LLMNR is desired, in which case UTF-8 characters should be used.

           Added in version 239.

       --service-address=BOOL
           Takes a boolean parameter. If true (the default), when doing a service lookup with
           --service the hostnames contained in the SRV resource records are resolved as well.

           Added in version 239.

       --service-txt=BOOL
           Takes a boolean parameter. If true (the default), when doing a DNS-SD service lookup
           with --service the TXT service metadata record is resolved as well.

           Added in version 239.

       --cname=BOOL
           Takes a boolean parameter. If true (the default), DNS CNAME or DNAME redirections are
           followed. Otherwise, if a CNAME or DNAME record is encountered while resolving, an
           error is returned.

           Added in version 239.

       --validate=BOOL
           Takes a boolean parameter; used in conjunction with query. If true (the default),
           DNSSEC validation is applied as usual — under the condition that it is enabled for the
           network and for systemd-resolved.service as a whole. If false, DNSSEC validation is
           disabled for the specific query, regardless of whether it is enabled for the network
           or in the service. Note that setting this option to true does not force DNSSEC
           validation on systems/networks where DNSSEC is turned off. This option is only
           suitable to turn off such validation where otherwise enabled, not enable validation
           where otherwise disabled.

           Added in version 248.

       --synthesize=BOOL
           Takes a boolean parameter; used in conjunction with query. If true (the default),
           select domains are resolved on the local system, among them "localhost", "_gateway",
           "_outbound", "_localdnsstub" and "_localdnsproxy" or entries from /etc/hosts. If false
           these domains are not resolved locally, and either fail (in case of "localhost",
           "_gateway" or "_outbound" and suchlike) or go to the network via regular
           DNS/mDNS/LLMNR lookups (in case of /etc/hosts entries).

           Added in version 248.

       --cache=BOOL
           Takes a boolean parameter; used in conjunction with query. If true (the default),
           lookups use the local DNS resource record cache. If false, lookups are routed to the
           network instead, regardless if already available in the local cache.

           Added in version 248.

       --zone=BOOL
           Takes a boolean parameter; used in conjunction with query. If true (the default),
           lookups are answered from locally registered LLMNR or mDNS resource records, if
           defined. If false, locally registered LLMNR/mDNS records are not considered for the
           lookup request.

           Added in version 248.

       --trust-anchor=BOOL
           Takes a boolean parameter; used in conjunction with query. If true (the default),
           lookups for DS and DNSKEY are answered from the local DNSSEC trust anchors if
           possible. If false, the local trust store is not considered for the lookup request.

           Added in version 248.

       --network=BOOL
           Takes a boolean parameter; used in conjunction with query. If true (the default),
           lookups are answered via DNS, LLMNR or mDNS network requests if they cannot be
           synthesized locally, or be answered from the local cache, zone or trust anchors (see
           above). If false, the request is not answered from the network and will thus fail if
           none of the indicated sources can answer them.

           Added in version 248.

       --search=BOOL
           Takes a boolean parameter. If true (the default), any specified single-label hostnames
           will be searched in the domains configured in the search domain list, if it is
           non-empty. Otherwise, the search domain logic is disabled. Note that this option has
           no effect if --type= is used (see above), in which case the search domain logic is
           unconditionally turned off.

           Added in version 239.

       --raw[=payload|packet]
           Dump the answer as binary data. If there is no argument or if the argument is
           "payload", the payload of the packet is exported. If the argument is "packet", the
           whole packet is dumped in wire format, prefixed by length specified as a little-endian
           64-bit number. This format allows multiple packets to be dumped and unambiguously
           parsed.

           Added in version 239.

       --legend=BOOL
           Takes a boolean parameter. If true (the default), column headers and meta information
           about the query response are shown. Otherwise, this output is suppressed.

           Added in version 239.

       --stale-data=BOOL
           Takes a boolean parameter; used in conjunction with query. If true (the default),
           lookups are answered with stale data (expired resource records) if possible. If false,
           the stale data is not considered for the lookup request.

           Added in version 254.

       --relax-single-label=BOOL
           Takes a boolean parameter; used in conjunction with query. If true, rules regarding
           routing of single-label names are relaxed. Defaults to false. By default, lookups of
           single label names are assumed to refer to local hosts to be resolved via local
           resolution such as LLMNR or via search domain qualification and are not routed to
           upstream servers as is. If this option is enabled these rules are disabled and the
           queries are routed upstream anyway. Also see the ResolveUnicastSingleLabel= option in
           resolved.conf(5) which provides a system-wide option that controls this behaviour.

           Added in version 256.

       --json=MODE
           Shows output formatted as JSON. Expects one of "short" (for the shortest possible
           output without any redundant whitespace or line breaks), "pretty" (for a pretty
           version of the same, with indentation and line breaks) or "off" (to turn off JSON
           output, the default).

       -j
           Equivalent to --json=pretty if running on a terminal, and --json=short otherwise.

       --no-pager
           Do not pipe output into a pager.

       -h, --help
           Print a short help text and exit.

       --version
           Print a short version string and exit.

COMPATIBILITY WITH RESOLVCONF(8)

       resolvectl is a multi-call binary. When invoked as "resolvconf" (generally achieved by
       means of a symbolic link of this name to the resolvectl binary) it is run in a limited
       resolvconf(8) compatibility mode. It accepts mostly the same arguments and pushes all data
       into systemd-resolved.service(8), similar to how dns and domain commands operate. Note
       that systemd-resolved.service is the only supported backend, which is different from other
       implementations of this command.

       /etc/resolv.conf will only be updated with servers added with this command when
       /etc/resolv.conf is a symlink to /run/systemd/resolve/resolv.conf, and not a static file.
       See the discussion of /etc/resolv.conf handling in systemd-resolved.service(8).

       Not all operations supported by other implementations are supported natively.
       Specifically:

       -a
           Registers per-interface DNS configuration data with systemd-resolved. Expects a
           network interface name as only command line argument. Reads resolv.conf(5)-compatible
           DNS configuration data from its standard input. Relevant fields are "nameserver" and
           "domain"/"search". This command is mostly identical to invoking resolvectl with a
           combination of dns and domain commands.

           Added in version 239.

       -d
           Unregisters per-interface DNS configuration data with systemd-resolved. This command
           is mostly identical to invoking resolvectl revert.

           Added in version 239.

       -f
           When specified -a and -d will not complain about missing network interfaces and will
           silently execute no operation in that case.

           Added in version 239.

       -x
           This switch for "exclusive" operation is supported only partially. It is mapped to an
           additional configured search domain of "~."  — i.e. ensures that DNS traffic is
           preferably routed to the DNS servers on this interface, unless there are other, more
           specific domains configured on other interfaces.

           Added in version 239.

       -m, -p
           These switches are not supported and are silently ignored.

           Added in version 239.

       -u, -I, -i, -l, -R, -r, -v, -V, --enable-updates, --disable-updates, --are-updates-enabled
           These switches are not supported and the command will fail if used.

           Added in version 239.

       See resolvconf(8) for details on those command line options.

EXAMPLES

       Example 1. Retrieve the addresses of the "www.0pointer.net" domain (A and AAAA resource
       records)

           $ resolvectl query www.0pointer.net
           www.0pointer.net: 2a01:238:43ed:c300:10c3:bcf3:3266:da74
                             85.214.157.71

           -- Information acquired via protocol DNS in 611.6ms.
           -- Data is authenticated: no

       Example 2. Retrieve the domain of the "85.214.157.71" IP address (PTR resource record)

           $ resolvectl query 85.214.157.71
           85.214.157.71: gardel.0pointer.net

           -- Information acquired via protocol DNS in 1.2997s.
           -- Data is authenticated: no

       Example 3. Retrieve the MX record of the "yahoo.com" domain

           $ resolvectl --legend=no -t MX query yahoo.com
           yahoo.com. IN MX    1 mta7.am0.yahoodns.net
           yahoo.com. IN MX    1 mta6.am0.yahoodns.net
           yahoo.com. IN MX    1 mta5.am0.yahoodns.net

       Example 4. Resolve an SRV service

           $ resolvectl service _xmpp-server._tcp gmail.com
           _xmpp-server._tcp/gmail.com: alt1.xmpp-server.l.google.com:5269 [priority=20, weight=0]
                                        173.194.210.125
                                        alt4.xmpp-server.l.google.com:5269 [priority=20, weight=0]
                                        173.194.65.125
                                        ...

       Example 5. Retrieve a PGP key (OPENPGP resource record)

           $ resolvectl openpgp zbyszek@fedoraproject.org
           d08ee310438ca124a6149ea5cc21b6313b390dce485576eff96f8722._openpgpkey.fedoraproject.org. IN OPENPGPKEY
                   mQINBFBHPMsBEACeInGYJCb+7TurKfb6wGyTottCDtiSJB310i37/6ZYoeIay/5soJjlMyf
                   MFQ9T2XNT/0LM6gTa0MpC1st9LnzYTMsT6tzRly1D1UbVI6xw0g0vE5y2Cjk3xUwAynCsSs
                   ...

       Example 6. Retrieve a TLS key (TLSA resource record)

           $ resolvectl tlsa tcp fedoraproject.org:443
           _443._tcp.fedoraproject.org IN TLSA 0 0 1 19400be5b7a31fb733917700789d2f0a2471c0c9d506c0e504c06c16d7cb17c0
                   -- Cert. usage: CA constraint
                   -- Selector: Full Certificate
                   -- Matching type: SHA-256

       "tcp" and ":443" are optional and could be skipped.

SEE ALSO

       systemd(1), systemd-resolved.service(8), systemd.dnssd(5), systemd-networkd.service(8),
       resolvconf(8)

NOTES

        1. RFC 6763 DNS-SD
           https://tools.ietf.org/html/rfc6763

        2. RFC 2782 SRV
           https://tools.ietf.org/html/rfc2782

        3. RFC 7929
           https://tools.ietf.org/html/rfc7929

        4. RFC 6698
           https://tools.ietf.org/html/rfc6698

        5. Link-Local Multicast Name Resolution
           https://tools.ietf.org/html/rfc4795

        6. Multicast DNS
           https://www.ietf.org/rfc/rfc6762.txt