[Dnsmasq-discuss] Reg: Info related to leases file

[Nehal J Wani]

On Tue, Sep 24, 2013 at 3:37 PM, Simon Kelley <simon at thekelleys.org.uk> wrote:
> On 24/09/13 10:48, Nehal J Wani wrote:
>>
>> On Tue, Sep 24, 2013 at 1:15 AM, Simon Kelley<simon at thekelleys.org.uk>
>> wrote:
>>>
>>> On 23/09/13 19:12, Nehal J Wani wrote:
>>>>
>>>>
>>>> If I am not wrong, there are 5 fields in a dnsmasq/<network-name>.leases
>>>> file:
>>>>
>>>> (i) Expiry time
>>>> (ii) MAC Address
>>>> (iii) IP Address
>>>> (iv) Hostname
>>>> (v) Client ID
>>>>
>>>> Q1: Is the above order fixed?
>>>> Q2: Which values from above can be NULL? (I know that leases contains
>>>> '*' for fields whose values are not known, but is it safe to assume
>>>> that it will be '*' for any value that is unknown?)
>>>>
>>>
>>> A1: Yes.
>>>
>>> A2: There will always be an expiry time and an IP address. The hostname
>>> and
>>> the client-id can be missing, in which case the fields will contain *.
>>>
>>> The Mac address may have a hardware type (rfc1060) appended like so:
>>>
>>> 02-01:02:03:04:05:06
>>>
>>> If the hardware type is 01 (ethernet), then it's omitted
>>>
>>> For IEEE1394 clients, the hardware type is 24, and the length of the MAC
>>> address is zero, so this appears as
>>>
>>> 24-
>>>
>>> See rfc2855 for details.
>>>
>>> There's also I completely different format for DHCPv6. If DHCPv6 is in
>>> use
>>> then the IPv4 leases will be terminated with a line like this:
>>>
>>> duid<server DUID>  as colon-separated hex
>>>
>>> and then there will follow the DHCPv6 leases as
>>>
>>> 1) Expiry time
>>> 2) IAID
>>> 3) IPv6 address
>>> 4) hostname
>>> 5) client DUID
>>>
>>>
>>
>> In case of DHCPv6, which of the above 5 fields can be missing (for
>> IPv6 addresses)?
>
>
> Only the hostname, which can be replaced with "*" if no hostname is known.
> All the others are required.
>
> For both IPv4 and IPv6 leases, the expiry time can be zero which means
> "never".
>

Out of the three types:  DUID-LLT, DUID-EN and DUID-LL, which one is
used by dnsmasq? I am asking because I want to confirm whether the MAC
address of the network interface is always a substring of the client
DUID or not.


> Cheers,
>
> Simon.
>
>
>
>>
>>>
>>>
>>>
>>>
>>> Cheers,
>>>
>>> Simon.
>>>
>>>
>>>
>>> _______________________________________________
>>> Dnsmasq-discuss mailing list
>>> Dnsmasq-discuss at lists.thekelleys.org.uk
>>> http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
>>
>>
>>
>>
>



-- 
Nehal J Wani
UG3, BTech CS+MS(CL)
IIIT-Hyderabad
http://commandlinewani.blogspot.com