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rblcheck - Online in the Cloud

Run rblcheck in OnWorks free hosting provider over Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator

This is the command rblcheck that can be run in the OnWorks free hosting provider using one of our multiple free online workstations such as Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator



rblckeck - DNSBL lookup utility


rblcheck [-s zone] [-S zone-file] [-c] [-tmvq] [-n nsaddr] address...


rblcheck is a simple command-line to perform DNSBL (DNS-based blocklists) lookups. For
every IP address (or a name, in which case it will be resolved to an address first), the
utility verifies whenever it is listed in a (list of) DNS blocklists specified with -s or
-S options, optionally obtains text assotiated with the listing (usually it is either some
description about the reason of the listing or an URL referring to such a description),
and displays results on standard output.

The program is implemented on top of udns(3) library.


The following options are recognized by rblcheck:

-s zone
add the given zone DNSBL name to the list of active zones.

-S zone-file
add list of zones from the named zone-file to the list of active zones (the file
specifies one zone as the first word on a line, empty lines and lines starting with
`#' character are ignored).

-c reset active zone list.

-v be more verbose, produce more detailed output.

-q the opposite for -v -- produce less detailed output.

-t obtain text for listed addresses.

-n nsaddr
Use the given nameserver (given as IPv4 or IPv6 address) instead of the default.
The same effect may be achieved by setting $NSCACHEIP environment variable.

-m stop after first hit, ie after the first address which is found to be listed.

-h print short help and exit.

If no -s, -S and -c options are given, rblcheck will try to obtain list of zones using
$RBLCHECK_ZONES environment variable, or ~/.rblcheckrc, or /etc/rblckechrc files, in that
order. If no zones are found, it will exit unsuccessefully.


When no addresses given are listed and no errors occured, rblcheck exits with code 0. If
at least one address is listed, rblcheck returns 100. In case of DNS errors, rblcheck
returns 2.


if no -s, -S or -c option is given, rblcheck tries this variable to obtain list of
DNSBL zones to check against.

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