1RESOLVECTL(1) resolvectl RESOLVECTL(1)
2
6 resolvectl, resolvconf - Resolve domain names, IPV4 and IPv6 addresses,
7 DNS resource records, and services; introspect and reconfigure the DNS
8 resolver
9
11 resolvectl [OPTIONS...] {COMMAND} [NAME...]
12
14 resolvectl may be used to resolve domain names, IPv4 and IPv6
15 addresses, DNS resource records and services with the systemd-
16 resolved.service(8) resolver service. By default, the specified list of
17 parameters will be resolved as hostnames, retrieving their IPv4 and
18 IPv6 addresses. If the parameters specified are formatted as IPv4 or
19 IPv6 operation the reverse operation is done, and a hostname is
20 retrieved for the specified addresses.
21 The program's output contains information about the protocol used for
23 the look-up and on which network interface the data was discovered. It
24 also contains information on whether the information could be
25 authenticated. All data for which local DNSSEC validation succeeds is
26 considered authenticated. Moreover all data originating from local,
27 trusted sources is also reported authenticated, including resolution of
28 the local host name, the "localhost" host name or all data from
29 /etc/hosts.
30
32 query HOSTNAME|ADDRESS...
33 Resolve domain names, IPv4 and IPv6 addresses.
34 service [[NAME] TYPE] DOMAIN
36 Resolve DNS-SD[1] and SRV[2] services, depending on the specified
37 list of parameters. If three parameters are passed the first is
38 assumed to be the DNS-SD service name, the second the SRV service
39 type, and the third the domain to search in. In this case a full
40 DNS-SD style SRV and TXT lookup is executed. If only two parameters
41 are specified, the first is assumed to be the SRV service type, and
42 the second the domain to look in. In this case no TXT RR is
43 requested. Finally, if only one parameter is specified, it is
44 assumed to be a domain name, that is already prefixed with an SRV
45 type, and an SRV lookup is done (no TXT).
46 openpgp EMAIL@DOMAIN...
48 Query PGP keys stored as OPENPGPKEY[3] resource records. Specified
49 e-mail addresses are converted to the corresponding DNS domain
50 name, and any OPENPGPKEY keys are printed.
51 tlsa [FAMILY] DOMAIN[:PORT]...
53 Query TLS public keys stored as TLSA[4] resource records. A query
54 will be performed for each of the specified names prefixed with the
55 port and family ("_port._family.domain"). The port number may be
56 specified after a colon (":"), otherwise 443 will be used by
57 default. The family may be specified as the first argument,
58 otherwise tcp will be used.
59 status [LINK...]
61 Shows the global and per-link DNS settings currently in effect. If
62 no command is specified, this is the implied default.
63 statistics
65 Shows general resolver statistics, including information whether
66 DNSSEC is enabled and available, as well as resolution and
67 validation statistics.
68 reset-statistics
70 Resets the statistics counters shown in statistics to zero. This
71 operation requires root privileges.
72 flush-caches
74 Flushes all DNS resource record caches the service maintains
75 locally. This is mostly equivalent to sending the SIGUSR2 to the
76 systemd-resolved service.
77 reset-server-features
79 Flushes all feature level information the resolver learnt about
80 specific servers, and ensures that the server feature probing logic
81 is started from the beginning with the next look-up request. This
82 is mostly equivalent to sending the SIGRTMIN+1 to the
83 systemd-resolved service.
84 dns [LINK [SERVER...]], domain [LINK [DOMAIN...]], default-route [LINK
86 [BOOL...]], llmnr [LINK [MODE]], mdns [LINK [MODE]], dnssec [LINK
87 [MODE]], dnsovertls [LINK [MODE]], nta [LINK [DOMAIN...]]
88 Get/set per-interface DNS configuration. These commands may be used
89 to configure various DNS settings for network interfaces. These
90 commands may be used to inform systemd-resolved or systemd-networkd
91 about per-interface DNS configuration determined through external
92 means. The dns command expects IPv4 or IPv6 address specifications
93 of DNS servers to use. The domain command expects valid DNS
94 domains, possibly prefixed with "~", and configures a per-interface
95 search or route-only domain. The default-route command expects a
96 boolean parameter, and configures whether the link may be used as
97 default route for DNS lookups, i.e. if it is suitable for lookups
98 on domains no other link explicitly is configured for. The llmnr,
99 mdns, dnssec and dnsovertls commands may be used to configure the
100 per-interface LLMNR, MulticastDNS, DNSSEC and DNSOverTLS settings.
101 Finally, nta command may be used to configure additional
102 per-interface DNSSEC NTA domains.
103 Commands dns, domain and nta can take a single empty string
105 argument to clear their respective value lists.
106 For details about these settings, their possible values and their
108 effect, see the corresponding settings in systemd.network(5).
109 revert LINK
111 Revert the per-interface DNS configuration. If the DNS
112 configuration is reverted all per-interface DNS setting are reset
113 to their defaults, undoing all effects of dns, domain,
114 default-route, llmnr, mdns, dnssec, dnsovertls, nta. Note that when
115 a network interface disappears all configuration is lost
116 automatically, an explicit reverting is not necessary in that case.
117
119 -4, -6
120 By default, when resolving a hostname, both IPv4 and IPv6 addresses
121 are acquired. By specifying -4 only IPv4 addresses are requested,
122 by specifying -6 only IPv6 addresses are requested.
123 -i INTERFACE, --interface=INTERFACE
125 Specifies the network interface to execute the query on. This may
126 either be specified as numeric interface index or as network
127 interface string (e.g. "en0"). Note that this option has no effect
128 if system-wide DNS configuration (as configured in /etc/resolv.conf
129 or /etc/systemd/resolve.conf) in place of per-link configuration is
130 used.
131 -p PROTOCOL, --protocol=PROTOCOL
133 Specifies the network protocol for the query. May be one of "dns"
134 (i.e. classic unicast DNS), "llmnr" (Link-Local Multicast Name
135 Resolution[5]), "llmnr-ipv4", "llmnr-ipv6" (LLMNR via the indicated
136 underlying IP protocols), "mdns" (Multicast DNS[6]), "mdns-ipv4",
137 "mdns-ipv6" (MDNS via the indicated underlying IP protocols). By
138 default the lookup is done via all protocols suitable for the
139 lookup. If used, limits the set of protocols that may be used. Use
140 this option multiple times to enable resolving via multiple
141 protocols at the same time. The setting "llmnr" is identical to
142 specifying this switch once with "llmnr-ipv4" and once via
143 "llmnr-ipv6". Note that this option does not force the service to
144 resolve the operation with the specified protocol, as that might
145 require a suitable network interface and configuration. The special
146 value "help" may be used to list known values.
147 -t TYPE, --type=TYPE, -c CLASS, --class=CLASS
149 Specifies the DNS resource record type (e.g. A, AAAA, MX, ...) and
150 class (e.g. IN, ANY, ...) to look up. If these options are used a
151 DNS resource record set matching the specified class and type is
152 requested. The class defaults to IN if only a type is specified.
153 The special value "help" may be used to list known values.
154 --service-address=BOOL
156 Takes a boolean parameter. If true (the default), when doing a
157 service lookup with --service the hostnames contained in the SRV
158 resource records are resolved as well.
159 --service-txt=BOOL
161 Takes a boolean parameter. If true (the default), when doing a
162 DNS-SD service lookup with --service the TXT service metadata
163 record is resolved as well.
164 --cname=BOOL
166 Takes a boolean parameter. If true (the default), DNS CNAME or
167 DNAME redirections are followed. Otherwise, if a CNAME or DNAME
168 record is encountered while resolving, an error is returned.
169 --search=BOOL
171 Takes a boolean parameter. If true (the default), any specified
172 single-label hostnames will be searched in the domains configured
173 in the search domain list, if it is non-empty. Otherwise, the
174 search domain logic is disabled.
175 --raw[=payload|packet]
177 Dump the answer as binary data. If there is no argument or if the
178 argument is "payload", the payload of the packet is exported. If
179 the argument is "packet", the whole packet is dumped in wire
180 format, prefixed by length specified as a little-endian 64-bit
181 number. This format allows multiple packets to be dumped and
182 unambiguously parsed.
183 --legend=BOOL
185 Takes a boolean parameter. If true (the default), column headers
186 and meta information about the query response are shown. Otherwise,
187 this output is suppressed.
188 -h, --help
190 Print a short help text and exit.
191 --version
193 Print a short version string and exit.
194 --no-pager
196 Do not pipe output into a pager.
197
199 resolvectl is a multi-call binary. When invoked as "resolvconf"
200 (generally achieved by means of a symbolic link of this name to the
201 resolvectl binary) it is run in a limited resolvconf(8) compatibility
202 mode. It accepts mostly the same arguments and pushes all data into
203 systemd-resolved.service(8), similar to how dns and domain commands
204 operate. Note that systemd-resolved.service is the only supported
205 backend, which is different from other implementations of this command.
206 Note that not all operations supported by other implementations are
207 supported natively. Specifically:
208 -a
210 Registers per-interface DNS configuration data with
211 systemd-resolved. Expects a network interface name as only command
212 line argument. Reads resolv.conf(5) compatible DNS configuration
213 data from its standard input. Relevant fields are "nameserver" and
214 "domain"/"search". This command is mostly identical to invoking
215 resolvectl with a combination of dns and domain commands.
216 -d
218 Unregisters per-interface DNS configuration data with
219 systemd-resolved. This command is mostly identical to invoking
220 resolvectl revert.
221 -f
223 When specified -a and -d will not complain about missing network
224 interfaces and will silently execute no operation in that case.
225 -x
227 This switch for "exclusive" operation is supported only partially.
228 It is mapped to an additional configured search domain of "~." —
229 i.e. ensures that DNS traffic is preferably routed to the DNS
230 servers on this interface, unless there are other, more specific
231 domains configured on other interfaces.
232 -m, -p
234 These switches are not supported and are silently ignored.
235 -u, -I, -i, -l, -R, -r, -v, -V, --enable-updates, --disable-updates,
237 --are-updates-enabled
238 These switches are not supported and the command will fail if used.
239 See resolvconf(8) for details on this command line options.
241
243 Example 1. Retrieve the addresses of the "www.0pointer.net" domain
244 $ resolvectl query www.0pointer.net
246 www.0pointer.net: 2a01:238:43ed:c300:10c3:bcf3:3266:da74
247 85.214.157.71
248 -- Information acquired via protocol DNS in 611.6ms.
250 -- Data is authenticated: no
251 Example 2. Retrieve the domain of the "85.214.157.71" IP address
253 $ resolvectl query 85.214.157.71
255 85.214.157.71: gardel.0pointer.net
256 -- Information acquired via protocol DNS in 1.2997s.
258 -- Data is authenticated: no
259 Example 3. Retrieve the MX record of the "yahoo.com" domain
261 $ resolvectl --legend=no -t MX query yahoo.com
263 yahoo.com. IN MX 1 mta7.am0.yahoodns.net
264 yahoo.com. IN MX 1 mta6.am0.yahoodns.net
265 yahoo.com. IN MX 1 mta5.am0.yahoodns.net
266 Example 4. Resolve an SRV service
268 $ resolvectl service _xmpp-server._tcp gmail.com
270 _xmpp-server._tcp/gmail.com: alt1.xmpp-server.l.google.com:5269 [priority=20, weight=0]
271 173.194.210.125
272 alt4.xmpp-server.l.google.com:5269 [priority=20, weight=0]
273 173.194.65.125
274 ...
275 Example 5. Retrieve a PGP key
277 $ resolvectl openpgp zbyszek@fedoraproject.org
279 d08ee310438ca124a6149ea5cc21b6313b390dce485576eff96f8722._openpgpkey.fedoraproject.org. IN OPENPGPKEY
280 mQINBFBHPMsBEACeInGYJCb+7TurKfb6wGyTottCDtiSJB310i37/6ZYoeIay/5soJjlMyf
281 MFQ9T2XNT/0LM6gTa0MpC1st9LnzYTMsT6tzRly1D1UbVI6xw0g0vE5y2Cjk3xUwAynCsSs
282 ...
283 Example 6. Retrieve a TLS key ("tcp" and ":443" could be skipped)
285 $ resolvectl tlsa tcp fedoraproject.org:443
287 _443._tcp.fedoraproject.org IN TLSA 0 0 1 19400be5b7a31fb733917700789d2f0a2471c0c9d506c0e504c06c16d7cb17c0
288 -- Cert. usage: CA constraint
289 -- Selector: Full Certificate
290 -- Matching type: SHA-256
291
293 systemd(1), systemd-resolved.service(8), systemd.dnssd(5), systemd-
294 networkd.service(8), resolvconf(8)
295
297 1. DNS-SD
298 https://tools.ietf.org/html/rfc6763
299 2. SRV
301 https://tools.ietf.org/html/rfc2782
302 3. OPENPGPKEY
304 https://tools.ietf.org/html/rfc7929
305 4. TLSA
307 https://tools.ietf.org/html/rfc6698
308 5. Link-Local Multicast Name Resolution
310 https://tools.ietf.org/html/rfc4795
311 6. Multicast DNS
313 https://www.ietf.org/rfc/rfc6762.txt
314systemd 245 RESOLVECTL(1)