GREPCIDR(1)						      General Commands Manual						       GREPCIDR(1)

NAME

       grepcidr -- Filter IP addresses matching IPv4 CIDR/network specification

SYNOPSIS

       grepcidr [-V]  [-c]  [-v]  [-e pattern | -f file]

DESCRIPTION

       This manual page documents briefly the grepcidr command.

       This manual page was written for the Debian distribution because the original program does not have a manual page.

       grepcidr  can  be  used to filter a list of IP addresses against one or more Classless Inter-Domain Routing (CIDR) specifications, or arbi-
       trary networks specified by an address range. As with grep, there are options to invert matching and load patterns from a  file.   grepcidr
       is capable of comparing thousands or even millions of IPs to networks with little memory usage and in reasonable computation time.

OPTIONS

       -V	 Show software version

       -c	 Display count of the matching lines, instead of showing the lines

       -v	 Invert the sense of matching, to select non-matching IP addresses

       -e	 Specify pattern(s) on command-line

       -f	 Obtain CIDR and range pattern(s) from file

EXAMPLES

       grepcidr -f ournetworks blocklist > abuse.log

       Find our customers that show up in blocklists

       grepcidr 127.0.0.0/8 iplog

       Searches for any localnet IP addresses inside the iplog file

       grepcidr "192.168.0.1-192.168.10.13" iplog

       Searches for IPs matching indicated range in the iplog file

       script | grepcidr -vf whitelist > blacklist

       Create a blacklist, with whitelisted networks removed (inverse)

       grepcidr -f list1 list2

       Cross-reference two lists, outputs IPs common to both lists

AUTHOR

       This  manual  page  was written by Ryan Finnie ryan@finnie.org for the Debian system (but may be used by others).  Permission is granted to
       copy, distribute and/or modify this document under the terms of the GNU General Public License, Version 2 any later  version  published	by
       the Free Software Foundation.

       On Debian systems, the complete text of the GNU General Public License can be found in /usr/share/common-licenses/GPL.

																       GREPCIDR(1)