Provided by: unbound-anchor_1.17.1-1_amd64 bug

NAME

       unbound-anchor - Unbound anchor utility.

SYNOPSIS

       unbound-anchor [opts]

DESCRIPTION

       Unbound-anchor  performs  setup  or update of the root trust anchor for DNSSEC validation.
       The program fetches the trust anchor with the method from  RFC7958  when  regular  RFC5011
       update fails to bring it up to date.  It can be run (as root) from the commandline, or run
       as part of startup scripts.  Before you start the unbound(8) DNS server.

       Suggested usage:

            # in the init scripts.
            # provide or update the root anchor (if necessary)
            unbound-anchor -a "/usr/share/dns/root.key"
            # Please note usage of this root anchor is at your own risk
            # and under the terms of our LICENSE (see source).
            #
            # start validating resolver
            # the unbound.conf contains:
            #   auto-trust-anchor-file: "/usr/share/dns/root.key"
            unbound -c unbound.conf

       This tool  provides  builtin  default  contents  for  the  root  anchor  and  root  update
       certificate files.

       It tests if the root anchor file works, and if not, and an update is possible, attempts to
       update the root anchor using the root update certificate.  It performs a  https  fetch  of
       root-anchors.xml  and  checks  the  results  (RFC7958),  if  all checks are successful, it
       updates the root anchor file.  Otherwise the root anchor file is unchanged.   It  performs
       RFC5011 tracking if the DNSSEC information available via the DNS makes that possible.

       It  does  not  perform  an update if the certificate is expired, if the network is down or
       other errors occur.

       The available options are:

       -a file
              The  root  anchor  key  file,  that  is  read  in  and  written  out.   Default  is
              /usr/share/dns/root.key.   If  the file does not exist, or is empty, a builtin root
              key is written to it.

       -c file
              The   root   update   certificate   file,   that   is   read   in.    Default    is
              /etc/unbound/icannbundle.pem.   If  the file does not exist, or is empty, a builtin
              certificate is used.

       -l     List the builtin root key and builtin root update certificate on stdout.

       -u name
              The server name, it connects to https://name.   Specify  without  https://  prefix.
              The  default  is  "data.iana.org".  It connects to the port specified with -P.  You
              can pass an IPv4 address or IPv6 address (no brackets) if you want.

       -S     Do not use SNI for the HTTPS connection.  Default is to use SNI.

       -b address
              The source address to bind to for domain resolution and contacting  the  server  on
              https.  May be either an IPv4 address or IPv6 address (no brackets).

       -x path
              The  pathname to the root-anchors.xml file on the server. (forms URL with -u).  The
              default is /root-anchors/root-anchors.xml.

       -s path
              The pathname to the root-anchors.p7s file on the server. (forms URL with -u).   The
              default  is  /root-anchors/root-anchors.p7s.  This file has to be a PKCS7 signature
              over the xml file, using the pem file (-c) as trust anchor.

       -n name
              The emailAddress for the Subject of the signer's certificate from the p7s signature
              file.  Only signatures from this name are allowed.  default is dnssec@iana.org.  If
              you pass "" then the emailAddress is not checked.

       -4     Use IPv4 for domain resolution and contacting the server on https.  Default  is  to
              use IPv4 and IPv6 where appropriate.

       -6     Use  IPv6  for domain resolution and contacting the server on https.  Default is to
              use IPv4 and IPv6 where appropriate.

       -f resolv.conf
              Use the given resolv.conf file.  Not enabled by default, but you could try to  pass
              /etc/resolv.conf  on  some  systems.  It contains the IP addresses of the recursive
              nameservers to use.  However, since this tool could be used to bootstrap that  very
              recursive  nameserver,  it  would  not  be useful (since that server is not up yet,
              since we are bootstrapping it).  It could be useful in a situation where  you  know
              an upstream cache is deployed (and running) and in captive portal situations.

       -r root.hints
              Use the given root.hints file (same syntax as the BIND and Unbound root hints file)
              to bootstrap domain resolution.  By default a list of builtin root hints  is  used.
              Unbound-anchor  goes  to  the network itself for these roots, to resolve the server
              (-u option) and to check the root DNSKEY records.  It does  so,  because  the  tool
              when  used  for  bootstrapping  the  recursive  resolver, cannot use that recursive
              resolver itself because it is bootstrapping that server.

       -R     Allow fallback from -f resolv.conf file to direct root servers  query.   It  allows
              you  to  prefer local resolvers, but fallback automatically to direct root query if
              they do not respond or do not support DNSSEC.

       -v     More verbose. Once prints informational messages, multiple times may  enable  large
              debug  amounts  (such  as full certificates or byte-dumps of downloaded files).  By
              default it prints almost nothing.  It also prints nothing on errors by default;  in
              that  case  the  original  root  anchor  file is simply left undisturbed, so that a
              recursive server can start right after it.

       -C unbound.conf
              Debug option to read unbound.conf into the resolver process used.

       -P port
              Set the port number to use for the https connection.  The default is 443.

       -F     Debug option to force update of the root anchor through downloading  the  xml  file
              and  verifying  it  with  the  certificate.  By default it first tries to update by
              contacting the DNS, which uses much less bandwidth, is much faster (200 msec not  2
              sec),  and  is  nicer  to  the deployed infrastructure.  With this option, it still
              attempts to do so (and may verbosely tell you), but then  ignores  the  result  and
              goes on to use the xml fallback method.

       -h     Show the version and commandline option help.

EXIT CODE

       This  tool  exits  with value 1 if the root anchor was updated using the certificate or if
       the builtin root-anchor was used.  It exits with code 0 if no update was necessary, if the
       update was possible with RFC5011 tracking, or if an error occurred.

       You can check the exit value in this manner:
            unbound-anchor -a "root.key" || logger "Please check root.key"
       Or something more suitable for your operational environment.

TRUST

       The  root  keys  and update certificate included in this tool are provided for convenience
       and under the terms of our license (see the LICENSE file in  the  source  distribution  or
       https://github.com/NLnetLabs/unbound/blob/master/LICENSE)   and  might  be  stale  or  not
       suitable to your purpose.

       By running "unbound-anchor -l" the  keys and certificate that are configured in  the  code
       are printed for your convenience.

       The  build-in  configuration can be overridden by providing a root-cert file and a rootkey
       file.

FILES

       /usr/share/dns/root.key
              The root anchor file, updated with 5011 tracking, and read  and  written  to.   The
              file is created if it does not exist.

       /etc/unbound/icannbundle.pem
              The  trusted  self-signed  certificate that is used to verify the downloaded DNSSEC
              root   trust   anchor.    You   can    update    it    by    fetching    it    from
              https://data.iana.org/root-anchors/icannbundle.pem  (and validate it).  If the file
              does not exist or is empty, a builtin version is used.

       https://data.iana.org/root-anchors/root-anchors.xml
              Source for the root key information.

       https://data.iana.org/root-anchors/root-anchors.p7s
              Signature on the root key information.

SEE ALSO

       unbound.conf(5), unbound(8).