[Dnsmasq-discuss] DHCP, how to ignore the client MAC address?

[smicha]

Hi all,

first of all, thank you for the grade software !!!
But I have a small questions regarding "dnsmasq" and DHCP requests.

Background:
We have running different, isolated test-landscapes. In each network a 
VM is running with dnsmasq, which do the DHCP/DNS task.
Some of the VM's in the landscape needs to have a "static" DHCP-IP, 
because a Firewall in front of the landscape routes traffic to the VM's 
(Rules are IP based)

So far so good.

Sometimes, when VM's (with the static DHCP-IP) has some problems and 
crash's and can not "release" there DHCP-IP, we need to re-deploy the 
same VM from our pool.
But, when the re-deployement process is starting, that new VM will have 
a different MAC Address per default. The Hostname is the same as before 
the old one had.

Now, the problem is begin, because dnsmasq have already a valid DHCP 
lease for the old (destroyed) VM and the new, re-deployed VM will get a 
different IP as expect.

I see in the dnsmasq logfile the following message:

       not using configured address 10.117.247.79 because it is leased to 
00:50:56:85:02:ff

The traffic from the firewall in front of, can reach the new VM (because 
the new VM does not have the correct expected IP).

In the past I use the tool "dhcp_release" to fix the issue, but now I 
ask is there an other way to fix this problem.


Question:
I there an option, that dnsmasq ignore the Client MAC address for 
"static" DHCP leases?


As far as I see, dnsmasq use a combination of "Hostname" and "MAC" for 
the DHCP leases.


I hope I could describe my problem understandable ;-)

Many Thanks
Michael