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Re: QUANTUM: DHCP issue with dnsmasq starting on network node under Folsom release on Ubuntu 12.04-1


Hi Rob there are no namespaces, the culprit was in fact ubuntu 12.04,
which installs dnsmasq with a LISTEN on ALL network connections
by default.

I just disabled its auto start and it is nor starting cleanly on the
network node when a job is scheduled.

Of course the VM's still doesn't get an IP address.

This is what i see.

I launch an instance.
   the *compute* node creates a TAP interface
   it plumbs vnet0 *under* this

At the same time the *network* node spawns TWO instances of dnsmasq  and
has the correct range of IPs for the subnet so declared and it binds
both of these (seems odd)
to the tap interface.

if I tcpdump for broadcasts I see INCOMING bootp requests from the
correct MAC address of the vnet0 interface on the compute node

if I tail -f the var/log/sysog file I see dnsmasq offering the first
free lease IP t the the correct MAC address of the vnet0 NIC

*vnet0 doesnt get its offered IP address and in fact I do NOT see the
offer being made from the network node BACK to the vnet0 on the compute

*No NIC on the VM.

It seems like the boroadcast from compute node NIC to the network node
and DNSmasq is OK, but the offered IP address is not sent back.

Any ideas welcome.

On 01/20/2013 01:49 PM, Robert Collins wrote:
> On 19 January 2013 19:17, Ivan <isb@xxxxxxxxxxxxxxx> wrote:
>> Hi all,
>>          I've hit a brick wall trying to get the dnsmasq process to bind
>> correctly and get itself ready to answer bootp/dhcp broadcasts.
> do you have net namespaces in use?
> (ip netns list)
> If not, I suspect your dhcp lease relay and dhcp-agent are binding to
> the same port and will conflict, as you see.
> -Rob