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Full Discussion: Delete Blank Lines Between DHCP Host Blocks
Top Forums Shell Programming and Scripting Delete Blank Lines Between DHCP Host Blocks Post 302258695 by cstovall on Saturday 15th of November 2008 11:39:21 AM
Old 11-15-2008
Bug Delete Blank Lines Between DHCP Host Blocks
Hi All,

I have a dhcpd.conf file that gets static hosts added and removed via a shell script. After sometime, there becomes huge gaps of space ( blank lines ) between each host block. I tried a couple of sed one-liners; but, I can't seem to get the output I'm looking for. Also, I would like to delete the blank lines between the host blocks interactively instead of piping to a file then doing a move back to the original file. Below is the output I'm looking for:

old dhcpd.conf:

host example1 {
hardware ethernet 00:00:00:00:00:01;
fixed-address 192.168.135.2;
option subnet-mask 255.255.255.0;
option routers 192.168.135.1;
next-server 192.168.135.210;
filename "linux-install/pxelinux.0";
}


host example2 {
hardware ethernet 00:00:00:00:00:02;
fixed-address 192.168.135.3;
option subnet-mask 255.255.255.0;
option routers 192.168.135.1;
next-server 192.168.135.210;
filename "linux-install/pxelinux.0";
}

host example3 {
hardware ethernet 00:00:00:00:00:03;
fixed-address 192.168.135.4;
option subnet-mask 255.255.255.0;
option routers 192.168.135.1;
next-server 192.168.135.210;
filename "linux-install/pxelinux.0";
}



new dhcpd.conf file:

host example1 {
hardware ethernet 00:00:00:00:00:01;
fixed-address 192.168.135.2;
option subnet-mask 255.255.255.0;
option routers 192.168.135.1;
next-server 192.168.135.210;
filename "linux-install/pxelinux.0";
}
host example2 {
hardware ethernet 00:00:00:00:00:02;
fixed-address 192.168.135.3;
option subnet-mask 255.255.255.0;
option routers 192.168.135.1;
next-server 192.168.135.210;
filename "linux-install/pxelinux.0";
}
host example3 {
hardware ethernet 00:00:00:00:00:03;
fixed-address 192.168.135.4;
option subnet-mask 255.255.255.0;
option routers 192.168.135.1;
next-server 192.168.135.210;
filename "linux-install/pxelinux.0";
}


Any help would be greatly appreciated. Thanks in advance!
 

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LEARN ABOUT DEBIAN

lire::firewall::ipfilterdlfconverter

IpfilterDlfConverter(3pm)				  LogReport's Lire Documentation				 IpfilterDlfConverter(3pm)

NAME

       Lire::Firewall::IpfilterDlfConverter - convert ipf (ipmon) logs to firewall DLF

DESCRIPTION

       Lire::Firewall::IpfilterDlfConverter converts Ipfilter logs into firewall DLF format.  Input for this converter is the standard ipf syslog
       log file as produced by ipmon. IP Filter is shipped with FreeBSD, OpenBSD (up to 2.9) and some other OS's.

EXAMPLE

       A ipfilter logfile which looks like

	Oct 30 07:42:29 rolle ipmon[16747]: 07:42:28.585962	ie0 @0:9
	 b 192.168.48.1,45085 -> 192.168.48.2,22 PR tcp len 20 64 -S OUT
	Oct 30 07:40:24 rolle ipmon[16747]: 07:40:23.631307	ep1 @0:6
	 b 192.168.26.5,113 -> 192.168.26.1,3717 PR tcp len 20 40 -AR OUT
	Oct 30 07:42:29 rolle ipmon[16747]: 07:42:28.585962	ie0 @0:9
	 b 192.168.48.1,45085 -> 192.168.48.2,22 PR tcp len 20 64 -S OUT
	Oct 30 07:44:11 rolle ipmon[16747]: 07:44:10.605416 2x	   ep1 @0:15
	 b 192.168.26.1,138 -> 192.168.26.255,138 PR udp len 20 257  IN
	Oct 30 07:44:34 rolle ipmon[16747]: 07:44:33.891869	ie0 @0:10
	 b 192.168.48.1,23406 -> 192.168.48.2,22 PR tcp len 20 64 -S OUT
	Oct 30 07:49:13 rolle ipmon[16747]: 07:49:12.554420	ep1 @0:15
	 b 210.132.100.117 -> 192.168.26.5 PR icmp len 20 56 icmp 3/3 for
	 192.168.26.5,61915 - 210.132.100.117,53 PR udp len 20 23040 IN
	Oct 30 07:50:23 rolle ipmon[16747]: 07:50:22.908107	ep1 @0:15
	 b 210.132.100.117 -> 192.168.26.5 PR icmp len 20 56 icmp 3/3 for
	 192.168.26.5,4480 - 210.132.100.117,53 PR udp len 20 19712 IN
	Oct 30 07:56:11 rolle ipmon[16747]: 07:56:11.113029 2x	   ep1 @0:15
	 b 192.168.26.1,138 -> 192.168.26.255,138 PR udp len 20 257  IN

       (that's: .... 'PR' protocol 'len' length_of_ip_headers_saved packetlength direction) will get converted to something like

	994398737 denied igmp 100.187.115.1 - ep1 LIRE_NOTAVAIL 
	 224.0.0.2 - 56
	994398861 denied igmp 100.187.115.1 - ep1 LIRE_NOTAVAIL 
	 224.0.0.1 - 56
	994398862 denied igmp 100.187.115.1 - ep1 LIRE_NOTAVAIL 
	 224.0.0.2 - 56
	994406849 denied udp 192.168.26.4 137 ie0 LIRE_NOTAVAIL 
	 192.168.26.255 137 116
	994406850 denied udp 192.168.26.4 137 ie0 LIRE_NOTAVAIL 
	 192.168.26.255 137 116
	994406866 denied udp 192.168.26.4 137 ie0 LIRE_NOTAVAIL 
	 192.168.26.255 137 98

SEE ALSO

       ipl(4) for description of log structure.

       The ipmon.c source (e.g. on

	http://www.openbsd.org/cgi-bin/cvsweb/~checkout~/ 
	 src/usr.sbin/ipmon/Attic/ipmon.c?rev=1.27& 
	 content-type=text/plain&hideattic=0

       ) for the specification of the log syntax.

       The IP Filter webpage on http://coombs.anu.edu.au/~avalon/ip-filter.html

AUTHOR

       Joost van Baal <joostvb@logreport.org>, Wessel Dankers <wsl@logreport.org>

VERSION

       $Id: IpfilterDlfConverter.pm,v 1.7 2009/03/15 08:10:55 vanbaal Exp $

COPYRIGHT

       Copyright (C) 2001-2003 Stichting LogReport Foundation LogReport@LogReport.org

       This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by
       the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

       This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

       You should have received a copy of the GNU General Public License along with this program (see COPYING); if not, check with
       http://www.gnu.org/copyleft/gpl.html.

Lire 2.1.1							    2009-03-15						 IpfilterDlfConverter(3pm)
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