Re: Linux & draft-gont-6man-slaac-dns-config-issues

[Jen Linkova <[e-mail]>]

On Wed, Mar 25, 2015 at 12:12 AM, Fernando Gont <[e-mail]> wrote:
> On 03/24/2015 12:24 PM, Jen Linkova wrote:
>> On Tue, Mar 24, 2015 at 5:22 PM, Fernando Gont <[e-mail]> wrote:
>>>> I agree that "<= 2x MaxRtrAdvInterval" limitation is way too strict
>>>> and we SHOULD fix this.
>
> It is not a network misconfiguration. It's a bug in the spec.

Again, I totally agree that the lifetime value probably should not be
limited to 2x MaxRtrAdvInterval
and it should be fixed. However I strongly object updating RFC6106 with
'The default value of AdvRDNSSLifetime and AdvDNSSLLifetime MUST be at
least 10*MaxRtrAdvInterval'.
I think we shall remove "<2x MaxRtrAdvInterval" limitation in 6106, that's it.

Bounding it to "> 10x MaxRtrAdvInterval" seems to be unnecessary overkill.

BTW most of the router implementations I've seen do allow specifying
lifetime values > 2MaxRtrAdvInterval, so I do believe that in many
cases the problem you are describing could be solved by properly
configuring routers.

>> And yes, it might be equal to Router Lifetime, which might be
>> significantly lower than 6000 sec (1 hr 40 mins) you are proposing.
>
> I think that the specific value that we use is the low-order bit (I can
> certainly live with 6000 sec). The high order bit is that there is a
> problem to be fixed.

I want be able to configure machines with lifetime much lower than
6000 secs, that's my problem with this draft. IMHO,  if LIfetime is <
MaxRtrAdvInterval - that's insane and should not be used, Lifetime <
3x MaxRtrAdvInterval is just "do it on your own risk if you really
know what you are doing", everything else is OK.


-- 
SY, Jen Linkova aka Furry