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Description of problem:

dnsmasq contains a bug where hostnames that begin with numbers inside the dhcp-hostsfile are not honored and are logged as "bad DHCP host name at line X"

This has been fixed upstream to be in accordance with RFC 1123 (see http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2013q3/007369.html)

Version-Release number of selected component (if applicable):

Name        : dnsmasq
Version     : 2.66
Release     : 14.el7_1
Architecture: x86_64

How reproducible: Always

Steps to Reproduce:
1. Add a host entry in the dnsmasq dhcp-host file where the name begins with a number, e.g.

fa:16:3e:2e:8c:2a,07bc483fe-c864-4d2d-8c8d-355943c20e08.mydomain.com.,10.254.0.4

2. Start dnsmasq

Actual results:

Error is logged as "bad DHCP host name at line"
host with associated mac address cannot receive a lease, dnsmasq logs error "no address available"

Expected results:

File is read without errors, dhcp requests succeed

Additional info:

The OpenStack folks might be interested in this as I ran into this bug when testing out the neutron ml2 dns extension driver.  

When using the dns extension driver, neutron uses the <instancename>.suffix in the dnsmasq host file as opposed to 'host-<IP>.suffix'

If the instance begins with a number, the aforementioned problem occurs and the instance is unable to get its dhcp lease from dnsmasq

A simple test to check whether your version is affected:

dnsmasq-2.66/src/dnsmasq --test --dhcp-host=02:22:22:22:22:22,192.0.2.2,0myhostname

Note: It doesn't test the actual functionality, that would need a configured interface and other options and `--test` would be removed.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2016-2421.html