MAN.9FRONT.ORG RTFM


     NDB(8)                                                     NDB(8)

     NAME
          query, ipquery, mkhash, mkdb, mkhosts, cs, csquery, dns,
          dnsquery, dnsdebug, dnsgetip, inform - network database

     SYNOPSIS
          ndb/query [ -acim ] [ -f dbfile ] [ -x netmtpt ] attr value
          [ rattr ]...
          ndb/ipquery attr value rattr...
          ndb/mkhash file attr
          ndb/mkdb
          ndb/mkhosts [ domain [ dbfile ] ]
          ndb/cs [ -46n ] [ -f dbfile ] [ -x netmtpt ]
          ndb/csquery [ -s ] [ /net/cs [ addr... ] ]
          ndb/dns [ -FnrLR ] [ -a maxage ] [ -c cert.pem ] [ -f dbfile
          ] [ -N target ] [ -x netmtpt ] [ -s [ addrs... ] ]
          ndb/dnsquery [ -x ] [ /net/dns ]
          ndb/dnsdebug [ -crdx ] [ -f dbfile ] [ [ @server ] domain-
          name [ type ] ]
          ndb/dnsgetip [ -ax ] domain-name
          ndb/inform [ -x netmtpt ]

     DESCRIPTION
          The network database holds administrative information used
          by network programs such as dhcpd(8), ipconfig(8), con(1),
          etc.

          Ndb/query searches the network database for an attribute of
          type attr and value value. If a single rattr is specified,
          only the value of the first matching pair with attribute
          rattr is printed.  Under -m, the values of all pairs with a
          rattr attribute within the first matching entry are printed.
          Under -a and with a single rattr, all values of pairs with a
          rattr attribute within all entries are printed.  If none or
          more than one rattr where specified, all entries matched by
          the search are printed in ndb(6) format.  When the -i flag
          is present, the type attribute attr and its value are relat-
          ing to systems with ip= tuples, and the search will return
          rattr attributes inherited from their corresponding ipnet=
          entries.  (see the ndbipinfo and csipinfo functions in
          ndb(2)). The -i flag requires at least one rattr and each
          rattr prefixed with a @ is resolved to an IP address.  When
          -c flag is specified, instead of opening the network data-
          base files directly, the connection server mounted on
          netmtpt is consulted.  The netmtpt can be changed using the
          -x option (default /net).  Without the -c flag, the network
          database is searched directly by opening dbfile
          (/lib/ndb/local by default).

          Ndb/ipquery uses ndbipinfo (see ndb(2)) to search for the
          values of the attributes rattr corresponding to the systems

     NDB(8)                                                     NDB(8)

          with entries of attribute type attr and value value.

          Ndb/inform sends an RFC2136 DNS inform packet to a name-
          server to associate the host's IP address with its DNS name.
          This is required if the domain's nameserver is a Microsoft
          Windows Active Directory controller.  The host's domain name
          will be sent to the AD controller unless a tuple of the form
          inform=xxx is found in the host's ndb entry.

        Database maintenance
          Ndb/mkhash creates a hash file for all entries with
          attribute attr in database file file. The hash files are
          used by ndb/query and by the ndb library routines.

          Ndb/mkdb is used in concert with awk(1) scripts to convert
          uucp systems files and IP host files into database files.
          It is very specific to the situation at Murray Hill.

          When the database files change underfoot, ndb/cs and ndb/dns
          track them properly.  Nonetheless, to keep the database
          searches efficient it is necessary to run ndb/mkhash when-
          ever the files are modified.  It may be profitable to con-
          trol this by a frequent cron(8) job.

          Ndb/mkhosts generates a BSD style hosts, hosts.txt, and
          hosts.equiv files from an ndb data base file specified on
          the command line (default /lib/ndb/local).  For local rea-
          sons the files are called hosts.1127, astro.txt, and
          hosts.equiv.

        Connection service
          Ndb/cs is a server used by dial(2) to translate network
          names.  It is started at boot time.  It finds out what net-
          works are configured by looking for /net/*/clone when it
          starts.  It can also be told about networks by writing to
          /net/cs a message of the form:

               add net1 net2 ...

          Ndb/cs also sets the system name in /dev/sysname if it can
          figure it out.  The options are:

          -4  Only look up IPv4 addresses (A records) when consulting
              DNS.  The default is to also look up v6 addresses (AAAA
              records).  Writing `ipv4' to /net/cs will toggle IP v4
              look-ups.
          -6  Only look up IPv6 addresses in DNS.  Writing `ipv6' to
              /net/cs toggles v6 lookups.
          -f  supplies the name of the data base file to use, default
              /lib/ndb/local.
          -n  causes cs to do nothing but set the system name.
          -x  specifies the mount point of the network.

     NDB(8)                                                     NDB(8)

          Ndb/csquery queries ndb/cs to see how it resolves addresses.
          Ndb/csquery prompts for addresses and prints what ndb/cs
          returns.  Server defaults to /net/cs.  If any addrs are
          specified, ndb/csquery prints their translations and immedi-
          ately exits.  The exit status will be nil only if all
          addresses were successfully translated.  The -s flag sets
          exit status without printing any results.

        Domain name service
          Ndb/dns serves ndb/cs and remote systems by translating
          Internet domain names.  Ndb/dns is started at boot time.  By
          default dns serves only requests written to /net/dns.  Pro-
          grams must seek to offset 0 before reading or writing
          /net/dns or /net/cs.  The options are:

          -a  sets the maximum time in seconds that an unreferenced
              domain name will remain cached.  The default is one hour
              (3600).
          -f  supplies the name of the data base file to use, default
              /lib/ndb/local.
          -n  whenever a DNS zone that we serve changes, send UDP
              NOTIFY messages to any dns slaves for that zone (see the
              `dnsslave' attribute below).
          -N  sets the goal for the number of domain names cached to
              target rather than the default of 8,000.
          -r  act as a resolver only: send `recursive' queries, asking
              the other servers to complete lookups.  If present,
              /env/DNSSERVER or /env/DOTSERVER must be a space-
              separated list of such DNS (or DoT) servers' IP
              addresses, otherwise optional ndb(6) dns attributes name
              DNS servers to forward queries to.  Note that when
              DOTSERVER is specified, DNSSERVER are ignored.
          -R  ignore the `recursive' bit on all incoming requests.  Do
              not complete lookups on behalf of remote systems.
          -L  ignore the `recursive' bit on incoming requests from
              non-local IP addresses.  IP addresses are local when
              they are contained within the network prefix of an
              interface.  This allows running as a authoritative
              server while also serving recursive queries for systems
              on local networks.
          -s  also answer domain requests sent to IP addrs on UDP/TCP
              port 53.  If no IP addrs are given, listen on any inter-
              face on network mount point netmtpt.
          -c  When a certificate cert.pem is specified, also listen on
              TCP port 853 and handle DNS requests over TLS.  Clients
              wanting to connect to this service must add the certifi-
              cate or public key thumbprint into /sys/lib/tls/dns.
          -x  specifies the mount point of the network.

          When the -r option is specified, the servers used come from
          the dns attribute in the database.  For example, to specify
          a set of dns servers that will resolve requests for systems

     NDB(8)                                                     NDB(8)

          on the network mh-net:

               ipnet=mh-net ip=135.104.0.0 ipmask=255.255.0.0
                    dns=ns1.cs.bell-labs.com
                    dns=ns2.cs.bell-labs.com
               dom=ns1.cs.bell-labs.com ip=135.104.1.11
               dom=ns2.cs.bell-labs.com ip=135.104.1.12

          The server for a domain is indicated by a database entry
          containing both a dom and a ns attribute.

               dom=
                    ns=A.ROOT-SERVERS.NET
                    ns=B.ROOT-SERVERS.NET
                    ns=C.ROOT-SERVERS.NET
               dom=A.ROOT-SERVERS.NET ip=198.41.0.4
               dom=B.ROOT-SERVERS.NET ip=128.9.0.107
               dom=C.ROOT-SERVERS.NET ip=192.33.4.12

          The last three lines provide a mapping for the server names
          to their ip addresses.  This is only a hint and will be
          superseded from whatever is learned from servers owning the
          domain.

        Authoritative Name Servers
          You can also serve a subtree of the domain name space from
          the local database.  You indicate subtrees that you would
          like to serve by adding an soa= attribute to the root entry.
          For example, the Bell Labs CS research domain is:

               dom=cs.bell-labs.com soa=
                    refresh=3600 ttl=3600
                    ns=plan9.bell-labs.com
                    ns=ns1.cs.bell-labs.com
                    ns=ns2.cs.bell-labs.com
                    mb=presotto@plan9.bell-labs.com
                    mx=mail.research.bell-labs.com pref=20
                    mx=plan9.bell-labs.com pref=10
                    dnsslave=nslocum.cs.bell-labs.com
                    dnsslave=vex.cs.bell-labs.com

          Here, the mb entry is the mail address of the person respon-
          sible for the domain (default postmaster).  The mx entries
          list mail exchangers for the domain name and refresh and ttl
          define the area refresh interval and the minimum TTL for
          records in this domain.  The dnsslave entries specify slave
          DNS servers that should be notified when the domain changes.
          The notification also requires the -n flag.

        Reverse Domains
          You can also serve reverse lookups (returning the name that
          goes with an IP address) by adding an soa= attribute to the

     NDB(8)                                                     NDB(8)

          entry defining the root of the reverse space.

          For example, to provide reverse lookup for all addresses in
          starting with `135.104' or `fd00::', ndb must contain a
          record like:

               dom=104.135.in-addr.arpa soa=
                    dom=d.f.ip6.arpa soa=    # special case, rfc 4193
                    refresh=3600 ttl=3600
                    ns=plan9.bell-labs.com
                    ns=ns1.cs.bell-labs.com
                    ns=ns2.cs.bell-labs.com

          Notice the form of the reverse address.  For IPv4, it's the
          bytes of the address range you are serving reversed and
          expressed in decimal, and with `.in-addr.arpa' appended.
          For IPv6, it's the nibbles (4-bit fields) of the address
          range you are serving reversed and expressed in hexadecimal,
          and with `.ip6.arpa' appended.  These are the standard forms
          for a domain name in a PTR record.

          If such an soa entry exists in the database, reverse
          addresses will automatically be generated from any IP
          addresses in the database that are under this root.  For
          example

               dom=ns1.cs.bell-labs.com ip=135.104.1.11

          will automatically create both forward and reverse entries
          for ns1.cs.bell-labs.com.  Unlike other DNS servers, there's
          no way to generate inconsistent forward and reverse entries.

        Classless reverse delegation
          Following RFC 2317, it is possible to serve reverse DNS data
          for IPv4 subnets smaller than /24.  Declare the non-/24 sub-
          net, the reverse domain and the individual systems.

          For example, this is how to serve RFC-2317 ptr records for
          the subnet `65.14.39.128/123'.

               ipnet=our-t1 ip=65.14.39.128 ipmask=/123
               dom=128.39.14.65.in-addr.arpa soa=
                    refresh=3600 ttl=3600
                    ns=ns1.our-domain.com
                    ns=ns2.our-domain.com
               ip=65.14.39.129 dom=router.our-domain.com

        Delegating Name Service Authority
          Delegation of a further subtree to another set of name
          servers is indicated by an soa=delegated attribute.

               dom=bignose.cs.research.bell-labs.com

     NDB(8)                                                     NDB(8)

                    soa=delegated
                    ns=anna.cs.research.bell-labs.com
                    ns=dj.cs.research.bell-labs.com

          Nameservers within the delegated domain (as in this example)
          must have their IP addresses listed elsewhere in ndb files.

        Wildcards, MX and CNAME records
          Wild-carded domain names can also be used.  For example, to
          specify a mail forwarder for all Bell Labs research systems:

               dom=*.research.bell-labs.com
                    mx=research.bell-labs.com

          `Cname' aliases may be established by adding a cname
          attribute giving the real domain name; the name attached to
          the dom attribute is the alias.  `Cname' aliases are
          severely restricted; the aliases may have no other
          attributes than dom and are daily further restricted in
          their use by new RFCs.

               cname=anna.cs.bell-labs.com dom=www.cs.bell-labs.com

          makes www....  a synonym for the canonical name anna.....

        Zone Transfers and TCP
          TCP clients requesting DNS zone transfer must be listed with
          a dnsslave attribute for the relevant domain.  A value of *
          means any client is accepted.

        DNS Queries and Debugging
          Ndb/dnsquery can be used to query ndb/dns to see how it
          resolves requests.  Ndb/dnsquery prompts for commands of the
          form

               [ ! ] domain-name request-type

          where request-type can be ip, ipv6, mx, ns, cname, ptr....
          In the case of the inverse query type, ptr, dnsquery will
          reverse the ip address and tack on the .in-addr.arpa if nec-
          essary.  If the command starts with an exclamation mark !
          then the response is returned in ndb(6) format.  The -x
          option switches ndb/dnsquery to query the dns server on
          /net.alt instead of /net.

          Ndb/dnsdebug is like ndb/dnsquery but bypasses the local
          server.  It communicates via UDP (and sometimes TCP) with
          the domain name servers in the same way that the local
          resolver would and displays all packets received.  The query
          can be specified on the command line or can be prompted for.
          The queries look like those of ndb/dnsquery with one addi-
          tion.  Ndb/dnsdebug can be directed to query a particular

     NDB(8)                                                     NDB(8)

          name server by the command @name-server.  From that point
          on, all queries go to that name server rather than being
          resolved by dnsdebug. The @ command returns query resolution
          to dnsdebug. Finally, any command preceded by a @name-server
          sets the name server only for that command.

          Normally dnsdebug uses the /net interface and the database
          file /lib/ndb/local.  The -f option supplies the name of the
          data base file to use.  The -r option is the same as for
          ndb/dns. The -x option directs dnsdebug to use the /net.alt
          interface and /lib/ndb/external database file.  The -c
          option enables caching which is handy for debugging the dns
          code.

          Ndb/dnsgetip resolves and prints A and AAAA records without
          consulting ndb/dns. By default, ndb/dnsgetip queries A
          records first and then AAAA records. As with ndb/dns,
          /env/DNSSERVER or ndb(6) dns attributes are used as the DNS
          server. The -a flag will return all records. The -x option
          switches ndb/dnsgetip to query the dns server through
          /net.alt instead of /net.

     EXAMPLES
          Look up helix in ndb.

               % ndb/query sys helix
               sys=helix dom=helix.research.bell-labs.com bootf=/mips/9powerboot
                    ip=135.104.117.31 ether=080069020427

          Look up plan9.bell-labs.com and its IP address in the DNS.

               % ndb/dnsquery
               > plan9.bell-labs.com ip
               plan9.bell-labs.com ip   204.178.31.2
               > 204.178.31.2 ptr
               2.31.178.204.in-addr.arpa ptr plan9.bell-labs.com
               2.31.178.204.in-addr.arpa ptr ampl.com
               >

          Print the names of all systems that boot via PXE.

               % ndb/query -a bootf /386/9bootpxe sys

     FILES
          /env/DNSSERVER       resolver's DNS servers' IP addresses
          /env/DOTSERVER       resolver's DNS over TLS servers' IP
                               addresses
          /sys/lib/tls/dns     resolver's certificate / public-key
                               thumbprints
          /lib/ndb/local       first database file searched
          /lib/ndb/local.*     hash files for /lib/ndb/local
          /srv/cs              service file for ndb/cs

     NDB(8)                                                     NDB(8)

          /net/cs              where /srv/cs gets mounted
          /srv/dns             service file for ndb/dns
          /net/dns             where /srv/dns gets mounted

     SOURCE
          /sys/src/cmd/ndb

     SEE ALSO
          ndb(2), ndb(6)

     BUGS
          Ndb databases are case-sensitive; ethernet addresses must be
          in lower-case hexadecimal.