Q. My DHCP server configured to assign static IPs to few Debian / Ubuntu Linux boxes using hostnames. My Windows 2000 and XP client computer sends hostname automatically. How do I send my hostname under Linux using dhcp client?
A. By default, the DHCP server requests the subnet-mask, broadcast-address, time-offset, routers, domain-name, domain-name-servers and host-name options. DHCP client configuration allows you to set a hostname using send host-name “hostname” parameter.
Linux dhcpclient configuration – dhclient.conf
dhclient.conf is a configuration file for DHCP client under Linux:
- Debian / Ubuntu Linux – /etc/dhcp3/dhclient.conf
- RHEL / Fedora / CentOS Linux – /etc/sysconfig/network-scripts/ifcfg-eth0 (for 1st DHCP network interface)

Debian / Ubuntu Linux DHCP Client Configuration
Open configuration file, enter:
$ sudo vi /etc/dhcp3/dhclient.conf
Set hostname as follows:
send host-name "vivek-laptop";
Save and close the file. Test new settings, enter:
$ sudo dhclient eth0
$ sudo dhclient interface-name
RHEL / CentOS / Fedora Linux DHCP Client Configuration
Open configuration file, enter:
# vi /etc/sysconfig/network-scripts/ifcfg-eth0
Append hostname, enter:
DHCP_HOSTNAME=vivek-laptop
Save and close the file. Restart network service:
# service network restart
Please refer to dhclient.conf man page for more information, enter:
$ man dhclient.conf
Just some additional points when I tried this on Ubuntu 12.10 Server. When editing the “dhclient.conf” file, I also had to comment out the the last two lines (shown below) for the technique above to work:
send host-name “mypreferredhostname”
#send host-name = gethostname();
#send fqdn.fqdn = gethostname();
For CentOS/Redhat 5/6, edit /etc/sysconfig/network file
and put :
HOSTNAME=myhostnamehere
and finally
# /etc/init.d/network restart
i set static ip on ubuntu 12.(client)
how to send hostname to dns server automatically
thanks
@Mr Xhark
In CentOS
/etc/init.d/network [restart/start] or /sbin/service network [start/restart] does not send the hostname when requesting ip, via dhcp, if the variable DHCP_HOSTNAME is not defined in /etc/sysconfig/network-scripts/ifcfg-ethX (where X is a number)
/sbin/service NetworkManager [restart/start] does send the hostname, even if not defined in ifcfg-ethX.