1unbound-anchor(8)                unbound 1.8.3               unbound-anchor(8)
2
3
4

NAME

6       unbound-anchor - Unbound anchor utility.
7

SYNOPSIS

9       unbound-anchor [opts]
10

DESCRIPTION

12       Unbound-anchor  performs  setup  or update of the root trust anchor for
13       DNSSEC validation.  The program  fetches  the  trust  anchor  with  the
14       method from RFC7958 when regular RFC5011 update fails to bring it up to
15       date.  It can be run (as root) from the commandline, or run as part  of
16       startup scripts.  Before you start the unbound(8) DNS server.
17
18       Suggested usage:
19
20            # in the init scripts.
21            # provide or update the root anchor (if necessary)
22            unbound-anchor -a "/var/lib/unbound/root.key"
23            # Please note usage of this root anchor is at your own risk
24            # and under the terms of our LICENSE (see source).
25            #
26            # start validating resolver
27            # the unbound.conf contains:
28            #   auto-trust-anchor-file: "/var/lib/unbound/root.key"
29            unbound -c unbound.conf
30
31       This  tool  provides  builtin  default contents for the root anchor and
32       root update certificate files.
33
34       It tests if the root anchor file works, and if not, and  an  update  is
35       possible, attempts to update the root anchor using the root update cer‐
36       tificate.  It performs a https fetch of root-anchors.xml and checks the
37       results  (RFC7958),  if  all checks are successful, it updates the root
38       anchor file.  Otherwise the root anchor file is unchanged.  It performs
39       RFC5011  tracking if the DNSSEC information available via the DNS makes
40       that possible.
41
42       It does not perform an update if the certificate  is  expired,  if  the
43       network is down or other errors occur.
44
45       The available options are:
46
47       -a file
48              The  root  anchor  key  file,  that  is read in and written out.
49              Default is /var/lib/unbound/root.key.   If  the  file  does  not
50              exist, or is empty, a builtin root key is written to it.
51
52       -c file
53              The  root  update certificate file, that is read in.  Default is
54              /etc/unbound/icannbundle.pem.  If the file does not exist, or is
55              empty, a builtin certificate is used.
56
57       -l     List the builtin root key and builtin root update certificate on
58              stdout.
59
60       -u name
61              The server name, it connects to https://name.   Specify  without
62              https://  prefix.   The default is "data.iana.org".  It connects
63              to the port specified with -P.  You can pass an IPv4 address  or
64              IPv6 address (no brackets) if you want.
65
66       -x path
67              The  pathname to the root-anchors.xml file on the server. (forms
68              URL with -u).  The default is /root-anchors/root-anchors.xml.
69
70       -s path
71              The pathname to the root-anchors.p7s file on the server.  (forms
72              URL  with  -u).   The default is /root-anchors/root-anchors.p7s.
73              This file has to be a PKCS7 signature over the xml  file,  using
74              the pem file (-c) as trust anchor.
75
76       -n name
77              The  emailAddress  for  the  Subject of the signer's certificate
78              from the p7s signature file.  Only signatures from this name are
79              allowed.   default  is dnssec@iana.org.  If you pass "" then the
80              emailAddress is not checked.
81
82       -4     Use IPv4 for domain resolution  and  contacting  the  server  on
83              https.  Default is to use IPv4 and IPv6 where appropriate.
84
85       -6     Use  IPv6  for  domain  resolution  and contacting the server on
86              https.  Default is to use IPv4 and IPv6 where appropriate.
87
88       -f resolv.conf
89              Use the given resolv.conf file.  Not enabled by default, but you
90              could try to pass /etc/resolv.conf on some systems.  It contains
91              the IP addresses of the recursive nameservers to use.   However,
92              since  this  tool could be used to bootstrap that very recursive
93              nameserver, it would not be useful (since that server is not  up
94              yet,  since  we  are bootstrapping it).  It could be useful in a
95              situation where you know an upstream cache is deployed (and run‐
96              ning) and in captive portal situations.
97
98       -r root.hints
99              Use  the  given  root.hints  file  (same  syntax as the BIND and
100              Unbound root hints file) to  bootstrap  domain  resolution.   By
101              default  a  list  of builtin root hints is used.  Unbound-anchor
102              goes to the network itself  for  these  roots,  to  resolve  the
103              server  (-u  option)  and  to check the root DNSKEY records.  It
104              does so, because the tool when used for bootstrapping the recur‐
105              sive resolver, cannot use that recursive resolver itself because
106              it is bootstrapping that server.
107
108       -R     Allow fallback from -f resolv.conf file to direct  root  servers
109              query.   It  allows  you to prefer local resolvers, but fallback
110              automatically to direct root query if they do not respond or  do
111              not support DNSSEC.
112
113       -v     More verbose. Once prints informational messages, multiple times
114              may enable large debug amounts (such  as  full  certificates  or
115              byte-dumps  of  downloaded  files).  By default it prints almost
116              nothing.  It also prints nothing on errors by default;  in  that
117              case  the  original root anchor file is simply left undisturbed,
118              so that a recursive server can start right after it.
119
120       -C unbound.conf
121              Debug option to read  unbound.conf  into  the  resolver  process
122              used.
123
124       -P port
125              Set  the  port  number  to  use  for  the https connection.  The
126              default is 443.
127
128       -F     Debug option to force update of the root  anchor  through  down‐
129              loading  the xml file and verifying it with the certificate.  By
130              default it first tries to update by contacting  the  DNS,  which
131              uses  much  less bandwidth, is much faster (200 msec not 2 sec),
132              and is nicer to the deployed infrastructure.  With this  option,
133              it  still  attempts  to  do so (and may verbosely tell you), but
134              then ignores the result and goes on  to  use  the  xml  fallback
135              method.
136
137       -h     Show the version and commandline option help.
138

EXIT CODE

140       This  tool  exits with value 1 if the root anchor was updated using the
141       certificate or if the builtin root-anchor was used.  It exits with code
142       0  if  no update was necessary, if the update was possible with RFC5011
143       tracking, or if an error occurred.
144
145       You can check the exit value in this manner:
146            unbound-anchor -a "root.key" || logger "Please check root.key"
147       Or something more suitable for your operational environment.
148

TRUST

150       The root keys and update certificate included in this tool are provided
151       for  convenience  and  under  the terms of our license (see the LICENSE
152       file   in   the   source    distribution    or    http://unbound.nlnet
153       labs.nl/svn/trunk/LICENSE)  and  might be stale or not suitable to your
154       purpose.
155
156       By running "unbound-anchor -l" the  keys and certificate that are  con‐
157       figured in the code are printed for your convenience.
158
159       The  build-in  configuration can be overridden by providing a root-cert
160       file and a rootkey file.
161

FILES

163       /var/lib/unbound/root.key
164              The root anchor file, updated with 5011 tracking, and  read  and
165              written to.  The file is created if it does not exist.
166
167       /etc/unbound/icannbundle.pem
168              The  trusted  self-signed certificate that is used to verify the
169              downloaded DNSSEC root trust  anchor.   You  can  update  it  by
170              fetching  it  from  https://data.iana.org/root-anchors/icannbun
171              dle.pem (and validate it).  If the file does  not  exist  or  is
172              empty, a builtin version is used.
173
174       https://data.iana.org/root-anchors/root-anchors.xml
175              Source for the root key information.
176
177       https://data.iana.org/root-anchors/root-anchors.p7s
178              Signature on the root key information.
179

SEE ALSO

181       unbound.conf(5), unbound(8).
182
183
184
185NLnet Labs                       Dec 11, 2018                unbound-anchor(8)
Impressum