NONAMED(8)						      System Manager's Manual							NONAMED(8)

NAME

       nonamed - not a name daemon, but acts like one

SYNOPSIS

       nonamed [-d[level]] [-p port] [-n address[/port]]

DESCRIPTION

       Nonamed	is  not  an Internet name daemon.  When started it immediately tries to find a real name daemon on the local network.  If it finds
       one then it will relay any DNS queries to that name daemon.  If it can't find one then it will do its best to answer simple  queries  using
       the /etc/hosts table for name to address translation.

       On  startup nonamed broadcasts up to five" simple UDP queries on the local network.  This is a somewhat nasty thing to do, because it makes
       all name servers on the net spring into action to answer the request.  The first name server to answer is used by  nonamed  to  answer  the
       queries	of  its  clients.  The broadcast search is repeated after an hour to give another name server a chance to be abused.  (It is quite
       normal for a host to use a remote name server.  The broadcasts are a bit unfriendly, but they only happen once an hour.)

       If a real name server is found then nonamed enters "relay mode", passing all queries on.  In relay mode the daemon cannot be  distinguished
       from a real DNS name daemon.

       Nonamed	accepts  both  UDP and TCP queries under Minix-vmd.  Under standard Minix only UDP queries are accepted.  256" relayed UDP queries
       can be outstanding before it forgets where the first one came from.

       In answer mode nonamed can answer simple DNS queries to translate a host name to an IP address, or an IP address to a host  name.   Suppose
       /etc/hosts looks like this:

	      127.0.0.1      localhost
	      192.9.200.1    darask.home.cs.vu.nl
	      192.9.200.2    burask.home.cs.vu.nl

       Then  queries  for  the host names listed can be answered with the IP addresses to the left of them.  If the name can't be found then it is
       retried with the domain name stripped of, this is because "localhost" is looked up  as  "localhost.home.cs.vu.nl"  in  the  above  example.
       Reverse lookups are answered with the first hostname on the line with the IP address.

       UDP  queries are immediately answered on startup if the answer can be found in the hosts file.  Failure answers, and answers to TCP queries
       are delayed until it decides that there are no real name servers out there.

       Nonamed employs several timeouts for efficient operation:

       If five" broadcasts, two seconds" apart fail to produce a name server on startup then it decides  that  there  are  no  real  name  servers
       around.

       After 1 hour" it will again look for a name server.  (We don't want to hog the same one indefinitely.)

       If no UDP reply is seen in .ds m1
	than  a  simple probe is sent the name server.	If that doesn't provoke an answer in two seconds" then it will look for a new name server.
       A failing TCP connection will also invoke a search, the TCP connection is then made to the new name server.  A client using UDP will  retry
       eventually,  a  client  using TCP will notice nothing but a short delay.  The daemon drops back into answer mode if the search fails and it
       has a hosts file with a "localhost" entry.

       It waits five minutes" for any action on a TCP stream before the connection is aborted.

       In answer mode it will generate data with a TTL (time to live) of 1 hour".

OPTIONS

       The options are only useful when debugging nonamed, although it can be very instructive to watch DNS queries being done.

       -d[level]
	      Set debugging level to level (a single digit, by default 1.)  Debug mode 1 makes nonamed decode and  display  the  DNS  queries  and
	      replies  that  it  receives,  sends  and	relays.   The  decoding  only handles the common cases.  In debug mode 2 it prints tracing
	      information about the internal jobs it executes.	In debug mode 3 it core dumps when an error causes  it	to  exit.   The  debugging
	      level may also be increased by 1 at runtime by sending signal SIGUSR1 or turned off (set to 0) with SIGUSR2.

       [-p port]
	      Port to use instead of the normal domain port.

       [-n address[/port]]
	      Use  this  IP  address  and port to find a real name server.  It can be used to make nonamed relay to another nonamed.  (They do not
	      listen to broadcasts, of course.)  You can run two daemons on one machine if you choose a new port number for one of them.  You  can
	      force nonamed out of relay mode by sending it a hangup signal.

FILES

       /etc/hosts     Hosts to address translation table when in answer mode.

SEE ALSO

       gethostbyname(3), resolver(3), hosts(5), set_net_default(8), boot(8), inetd(8), irdpd(8), rarpd(8).

NOTES

       You can specify a remote name server in /etc/resolv.conf to circumvent nonamed.	But then you lose its talent for automatically finding new
       name servers when the remote name server becomes unreachable.

       Don't add a "localhost" entry to the hosts file if there are remote name servers.  It makes nonamed drop back in answer	mode  on  a  flaky
       network.

BUGS

       If  you	can  get  a  remote nonamed to listen to your name server then you can make it believe anything you want to.  You need access to a
       machine on the same subnet of course.

AUTHOR

       Kees J. Bot (kjb@cs.vu.nl)

																	NONAMED(8)