[Dnsmasq-discuss] [BUG] Bogus IP address in the syslog messages

[Simon Kelley]

Sergei Zhirikov wrote:
> On 2010-02-20 17:21, Simon Kelley wrote:
>> Sergei Zhirikov wrote:
>>> As I said, there is only one IP address. I have also used tcpdump
>>> to watch both DHCP and DNS communication. The address 216.230.6.8
>>> does not show up anywhere. (As a sidenote: I found it a bit
>>> surprising that despite "not giving name wafer ..." dnsmasq
>>> returns that same host name in the DHCPACK message to the client)
>>> 
>> The name didn't go into the DNS, but it's still what the client is 
>> called or called itself in the DHCP transaction, and the name is
>> matched against dhcp-host lines, so it's useful information to
>> have.
>> 
> Yes, it is certainly useful information. But I don't think it is wise
> to return it to the client. Doing that makes the client believe that
> it can be reached from the outside at the host name it has requested,
> while that is not true. -- Sergei.
> 

A valid point, but the alternative just adds even more uncertainty to
the effects of such a mis-configuration. The client may have supplied
the name, if it doesn't get returned in the DHCPACK, it will probably
continue to use it anyway. On the other hand the name may have come from
dnsmasq, and not putting it in the DHCPACK will leave the client nameless.

I think it's best to decouple the DHCP part and the DNS part as much as
possible, but it's a marginal decision.

Simon.