11-15-2008
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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dhcp(5) Standards, Environments, and Macros dhcp(5)
NAME
dhcp - Dynamic Host Configuration Protocol
DESCRIPTION
Dynamic Host Configuration Protocol (DHCP) enables host systems in a TCP/IP network to be configured automatically for the network as they
boot. DHCP uses a client/server mechanism: servers store configuration information for clients, and provide that information upon a
client's request. The information can include the client's IP address and information about network services available to the client.
This manual page provides a brief summary of the Solaris DHCP implementation.
Solaris DHCP Client
The Solaris DHCP client is implemented as background daemon, dhcpagent(1M). This daemon is started automatically during bootup if there
exists at least one dhcp.interface file in /etc. Only interfaces with a corresponding /etc/dhcp.interface file are automatically configured
during boot. Network parameters needed for system configuration during bootup are extracted from the information recieved by the daemon
through the use of the dhcpinfo(1) command. The daemon's default behavior can be altered by changing the tunables in the /etc/default/dhc-
pagent file. The daemon is controlled by the ifconfig(1M) utility. Check the status of the daemon using the netstat(1M) and ifconfig(1M)
commands.
Solaris DHCP Server
The Solaris DHCP server is implemented as a background daemon, in.dhcpd(1M). This daemon can deliver network configuration information to
either BOOTP or DHCP clients. The Solaris DHCP service can be managed using the dhcpmgr(1M) GUI or the command line utilities dhcpcon-
fig(1M), dhtadm(1M), and pntadm(1M).
DHCP Configuration Tables
The Solaris DHCP server stores client configuration information in the following two types of tables:
dhcptab tables Contain macros and options (also known as symbols), used to construct a package of configuration information to
send to each DHCP client. There exists only one dhcptab for the DHCP service. The dhcptab(4) can be viewed and mod-
ified using the dhtadm(1M) command or dhcpmgr(1M) graphical utility. See dhcptab(4) for more information about the
syntax of dhcptab records. See dhcp_inittab(4) for more information about the DHCP options and symbols.
DHCP network tables DHCP network tables, which contain mappings of client IDs to IP addresses and parameters associated with those
addresses. Network tables are named with the IP address of the network, and can be created, viewed, and modified
using the pntadm command or dhcpmgr graphical utility. See dhcp_network(4) for more information about network
tables.
SEE ALSO
dhcpinfo(1), dhcpagent(1M), dhcpconfig(1M), dhcpmgr(1M), dhtadm(1M), ifconfig(1M), in.dhcpd(1M), netstat(1M), pntadm(1M), syslog(3C),
dhcp_network(4), dhcptab(4), dhcpsvc.conf(4), dhcp_inittab(4), dhcp_modules(5)
Solaris DHCP Service Developer's Guide
Alexander, S., and R. Droms. RFC 2132, DHCP Options and BOOTP Vendor Extensions. Silicon Graphics, Inc. Bucknell University. March 1997.
Droms, R. RFC 1534, Interoperation Between DHCP and BOOTP. Bucknell University. October 1993.
Droms, R. RFC 2131, Dynamic Host Configuration Protocol. Bucknell University. March 1997.
Wimer, W. RFC 1542, Clarifications and Extensions for the Bootstrap Protocol. Carnegie Mellon University. October 1993.
SunOS 5.10 13 Mar 2001 dhcp(5)