Fedora/Ubuntu issue with assigned IP by dhcp server.

In the recent versions of Fedora/Ubuntu, I found that if the DHCP server assigns a reserved address, the address is not applied to the system. Finally I found that adding the below in /etc/dhcp/dhclient.conf, would fix the issue.

send dh-client-identifier = hardware;

dnsmasq – use with Network Manager.

Niles Machine Company
Niles Machine Company (Photo credits: roadtrafficsigns.com)


Well if you have not heard about dnsmasq:


Dnsmasq is lightweight, easy to configure DNS forwarder and DHCP server.
It is designed to provide DNS and, optionally, DHCP, to a small network.
It can serve the names of local machines which are not in the global
DNS. The DHCP server integrates with the DNS server and allows machines
with DHCP-allocated addresses to appear in the DNS with names configured
either in each host or in a central configuration file. Dnsmasq supports
static and dynamic DHCP leases and BOOTP for network booting of diskless


and for the installation :


sudo yum install dnsmasq


So, now that it is installed, all you need to do is add the following in file: /etc/NetworkManager/NetworkManager.conf




in the main section. Restart your network manager using sysctl and you should see that command:


dig google.com


should show result like below:


google.com. 185 IN A
google.com. 185 IN A
google.com. 185 IN A
google.com. 185 IN A
;; Query time: 50 msec
;; WHEN: Mon Jan 14 17:16:39 2013
;; MSG SIZE rcvd: 215


If it does not, then you might want to add a dispatcher to Network Manager that adds localhost to your “/etc/resolv.conf” file. And here is the name of the file – /etc/NetworkManager/dispatcher.d/localhost-prepend and the contents


# Prepend localhost to resolv.conf for dnsmasq

if [[ ! $(grep /etc/resolv.conf) ]]; then
  sed -i '1s|^|nameserver|' /etc/resolv.conf


Thats all there is to it 🙂



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