NAME

       tinydyndns-update - update TYPE A record in data.cdb

SYNOPSIS

       tinydyndns-update fqdn dynip

DESCRIPTION

       tinydyndns-update  changes  the data of a TYPE A record in data.cdb in the current directory.  Other than
       tinydns-data(8), tinydndns-update does not know about  the  source  file  data  but  changes  the  binary
       database data.cdb directly.

       First  tinydyndns-update checks if the given fqdn has a TYPE A record in data.cdb.  Then it checks if the
       given IP address differs from the one in the TYPE A record in data.cdb,  or  if  the  record's  timestamp
       should  be  updated.  Finally if data.cdb needs to change, tinydyndns-update copies data.cdb to data.tmp,
       changes the IP address of the TYPE A record of fqdn to dynip in data.tmp, optionally adjusts time-to-live
       or time-to-die, and renames data.tmp to data.cdb.

ENVIRONMENT

       TTL    time-to-live.   The  environment  variable TTL overrides the default time-to-live in seconds (0 if
              TTD is set, otherwise 5).  If TTL is not set or zero, the time-to-live  of  the  record  will  not
              change.  $TTL must be an integer.

       TTD    time-to-die.   $TTD  must  be  an  integer,  specifying  a  number of seconds.  If TTD is set, the
              timestamp of the record is set to the current time plus $TTD seconds, and TTL is set  to  zero  by
              default,  so that tinydns(8) interpretes the timestamp as time-to-die.  Note: you probably want to
              adjust SOA ttl, or create a wildcard record, to prevent DNS caches  from  caching  nxdomain,  when
              using this feature.

       LOC    location.   $LOC must be two characters long.  If LOC is set, it specifies the client location for
              records to be updated.

EXIT CODES

       If tinydyndns-update cannot find a TYPE A record for fqdn in data.cdb, it prints a warning and exits 114.

       If dynip does not differ from the IP address  of  the  TYPE  A  record  of  fqdn  in  data.cdb,  and  the
       environment variable TTD is not set, tinydyndns-update prints a note and exits 0.

       tinydyndns-update exits 100 if it has trouble opening data.cdb, and leaves data.cdb unchanged.

       tinydyndns-update exits 111 on temporary error, and leaves data.cdb unchanged.

       If data.cdb was changed successfully, tinydyndns-update exits 0.

FILES

        ./data.cdb
        ./data.tmp

SEE ALSO

       tinydyndns-data(8), tinydyndns-conf(8)

       http://smarden.org/tinydyndns/

AUTHOR

       Gerrit Pape <pape@smarden.org>

                                                                                            tinydyndns-update(8)