NAME

       rblcheck - check if an IP address is blacklisted

SYNOPSIS

       rblcheck [-qtlcvh?] [-s <service>] <address> [ <address> ... ]

DESCRIPTION

       rblcheck  is  a  very  basic  interface  to  DNSBL  listings such as those operated by The
       Spamhaus Project or Spamcop.

       The general idea behind DNSBL listings is rapid lookup of  IP  addresses  using  DNS  (for
       example,  for blacklisting IP addresses because of abuse). Each IP address is reversed and
       has a domain name attached to it; for example,  the  IP  address  127.0.0.2  would  become
       2.0.0.127,  and  then  a  domain such as "relays.visi.com" would be added to it. You would
       then try to resolve the result (ie.  2.0.0.127.relays.visi.com); if you receive a positive
       reply,  then you know that the address is listed. Further information can also be queried,
       such as text descriptions of why the address was listed.

OPTIONS

       -q     Quiet mode; outputs only matching IP address(es) - use return code (see below).

       -t     Print a TXT record, if any.

       -m     Stop checking after first address match in any list.

       -l     List default DNSBL services to check.

       -c     Clear the current list of DNSBL services.

       -s <service>
              Toggle service in the DNSBL list.

       -h, -? Display the help message.

       -v     Display version information.

       <address>
              An IP address to look up; specify `-' to  read  multiple  addresses  from  standard
              input.

RETURN CODES

       When invoked, rblcheck returns either 0 (to indicate error, or that the address was not in
       any of the listings), or a positive number (indicating the number of listings that the  IP
       address was found in).

SEE ALSO

       /usr/share/doc/rblcheck/, esp. /usr/share/doc/rblcheck/rblcheck.txt.gz

COPYRIGHT

       Copyright © 1997, 1998, 1999, 2000, 2001 Edward S. Marshall

       Man  page  created for the Debian Project with the help of help2man(1) based on the output
       of  `rblcheck   -h`   and   the   above   mentioned   text   file   by   Gregor   Herrmann
       <gregor+debian@comodo.priv.at>.