[Dnsmasq-discuss] Sending RA without dhcp-range

[Simon Kelley]

On 17/01/14 14:30, Shixiong Shang wrote:
> Just think out loud, can I use those modes with “—dhcp-range” so RA
> will be sent, and then use “--no-dhcp-interface=“ to disable DHCPv6
> on the corresponding interface?

No. --no-dhcp-interface= will disable RA too. There's no seperate 
access-control for RA, it uses the same parameters as DHCP

See my previous reply, there's no need to do this.


Cheers,

Simon.

>
> :D
>
> Shixiong
>
>
>
> On Jan 17, 2014, at 9:21 AM, Shixiong Shang
> <sparkofwisdom.cloud at gmail.com> wrote:
>
>> Hi, Simon and Albert:
>>
>> Thank both of you for quick response!
>>
>> According to the man page online, the mode like “ra-only”, and
>> “ra-stateless” are only used as part of “dhcp-range” option.
>> However, this will also turn dnsmasq to DHCPv6 server, which I try
>> to avoid. Would you please help me clarify how I can send RA on
>> specific interfaces with the right flags? The only thing I can
>> think of is leveraging “—ra-param”, but it doesn’t have place to
>> put in mode keywords…..
>>
>> Thanks again!
>>
>> Shixiong
>>
>>
>>
>>
>>
>>
>>
>> On Jan 17, 2014, at 5:49 AM, Simon Kelley <simon at thekelleys.org.uk>
>> wrote:
>>
>>> On 17/01/14 06:10, Albert ARIBAUD wrote:
>>>> Le 17/01/2014 05:30, Shixiong Shang a écrit :
>>>>> Hi, experts:
>>>>>
>>>>> Is it possible that dnsmasq can send out RA with either A=0,
>>>>> MO=1 (i.e. for DHCPv6 Stateful), or AO=1, M=0 (i.e. for
>>>>> DHCPv6 Stateless) WITHOUT dhcp-range? What I am trying to
>>>>> achieve here is using dnsmasq to send out RA to trigger
>>>>> DHCPv6 Stateful or DHCPv6 Stateless mode without acting as
>>>>> DHCPv6 server. Based on my reading, I am under the impression
>>>>> that “—enable-ra” must be used with “—dhcp-range”. Otherwise,
>>>>> dnsmasq will not send RA…..
>>>>
>>>> You are right about having to add enable-ra.
>>>>
>>>> However there is a syntax of dhcp-range which will not cause
>>>> DHCPv6.
>>>>
>>>> As per 'man dnsmasq' (search for 'dhcp-range'), the possible
>>>> modes for IPv6 ranges include 'ra-only', which will previsely
>>>> enable RAs without enabling any DHCP.
>>>>
>>>
>>> Neither of you are completely right.
>>>
>>> enable-ra causes RA with A=0 and M = 1  O = 1 on every interface
>>> that's doing DHCP, just to instruct the clients to do stateful
>>> DHCP. It's intended as a simple option for systems which don't
>>> use RA at all.
>>>
>>> You don't need to set enable-ra at all to do RA on specific
>>> interfaces with other flag combinations, ie
>>>
>>> ra-only A=1 M=0 O=0 slaac   A=1 M=1 O=1 ra-stateless A=1 M=0 O=1
>>>
>>> Cheers,
>>>
>>> Simon.
>>>
>
>