[atlas] IPv6 and Atlas probe v3

On 7/16/2013 at 5:38 PM Philip Homburg wrote:

|Hi Mike,
|
|On 2013/07/16 17:23 , Mike. wrote:
|>
|>  	Static Enabled 	Probe Knows 	Probe Uses 	Last Static Address Given
|> IPv6 		V			V			V       2001:470:xxx:xxx::xxx
|> DNS 		V			V			X	  2001:470:20::2 
|>
|>
|>
|> Question #1:  Why is there an "X" for DNS in the "Probe Uses"
column?
|> Is there something wrong with that DNS server?  
|
|The probe constructs an /etc/resolv.conf from either DHCP or the
|statically configured DNS resolvers. In practice it means that DHCP
will
|win. When the probe connects to a controller it reports which DNS
|resolvers it is using.
|
|So the 'X' means that the probe is not using the DNS resolver you
|configured but instead uses the ones from DHCP.


That makes sense.



|>
|> "...As of now, we have no way of preventing the probe from accepting
|> RAs. So if there is an IPv6 (rogue) RA on you network, it can/will
|> override part of the static configuration. We're unsure if this will
|> change in the future. ..."
|>
|>
|> I do have RA support on the subnet, though I would not classify it
as
|> "rogue".  :)    The RA provides the IPv6 prefix, prefix length, and
the
|> IPv6 address of the recursive DNS server.  This RA support has been
|> used by another box on the subnet, and it seems to work fine.
|>
|>
|> Question #2: Does the Atlas v3 probe use RA if they are present?
|
|Yes. If the probe receives a RA that directs the probe to configure an
|address then it will just do that even if it already has a statically
|configure IPv6 address.
|
 =============


Excellent, that is what I wanted to occur (i.e., the probe using the
prefix obtained via RA).  So far, using the RA for configuration, the
probe appears to be doing fine with IPv6 tasks.


As a suggestion, maybe the fact that the probe can use RA to configure
an IPv6 address could be mentioned in an appropriate area of the
documentation or FAQ?


In any case, thanks for the quick reply!

Mike.