[radvd-devel-l] RDNSS Option

Pekka Savola pekkas at netcore.fi
Thu Mar 9 12:49:57 EST 2006

Thanks Mickael, one comment below..

On Thu, 9 Mar 2006, Mickaël Guérin wrote:
>> +RDNSS (Recursive DNS server) definitions are of the form:
>> +
>> +.nf
>> +.BR "rdnss " "ip " {
>> +    list of rdnss specific options
>> +.B };
>> +.fi
>> ==> If I understand correctly, the syntax is:
>> RDNSS ip1 [ip2] [ip3] {
>>  ...
>> }
>> or something?  And there can be only one RDNSS definition under
>> an interface's configuration.   Is this true?
> Maybe should i explain this in the documentation :)
> you can specify only 1 IP per rdnss section, but you could put many
> rdnss sections. (dns servers are grouped during the parsing of the
> configuration file depending if the options allow it).

However, the lifetime and preference values are the same for all the 
DNS server addresses sent using one option, right?

So, it would be more logical to allow syntax like

RDNSS ip1 [ip2] [ip3] { lifetime 60; ... };

  or alternatively,

RNDSS { address ip1; address ip2; address ip3; lifetime 60; ... };

(that way, there's no need to specify multiple options, and check that 
the lifetime/preference is the same for all the addresses, etc.) ?

Note that in theory the spec allows the following config syntax:

RDNSS ip1 { lifetime 60; };
RDNSS ip2 { lifetime 30; };

but this would result in sending out two RDNSS options instead of one, 
and this seems unreasonably complicated and isn't really needed, so
I don't think it needs to be supported.  Do you agree?

How do you feel about this?

Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings

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