Re: [dhcwg] [EXTERNAL] Question to DHCPv6 Relay Implementors regarding draft-ietf-dhc-dhcpv6-pd-relay-requirements

["Templin (US), Fred L" <[e-mail]>]

BTW, if people have concerns about what I am doing vis-à-vis DHCPv6 PD they
should look at the AERO and OMNI specs and comment there directly. You may
find that some things that are discussed fully in document "A" are not touched
on hardly at all in document "O" (and vice-versa). I apologize for that; the long
term goal is that the OMNI spec becomes fully self-contained while the AERO
spec depends normatively on OMNI. Some deck chairs may yet need to be
shuffled to make that happen.

Fred

> -----Original Message-----
> From: ipv6 [mailto:[e-mail]] On Behalf Of Templin (US), Fred L
> Sent: Wednesday, October 07, 2020 7:27 AM
> To: [e-mail]
> Cc: dhcwg <[e-mail]>; v6ops list <[e-mail]>; 6man WG <[e-mail]>
> Subject: RE: [dhcwg] [EXTERNAL] Question to DHCPv6 Relay Implementors regarding draft-ietf-dhc-dhcpv6-pd-relay-requirements
> 
> Ole, are you talking about the amnesiac client case - such as, the client reboots
> and then comes back to life again with no memory of its past lifetime? Our
> lease lifetimes are short - generally about 30 seconds - so any stale leases
> should be very transient. But, our relays also retain knowledge about the
> client<->server interactions and in some sense act as a proxy for the client.
> So, the relay itself will clean up after an amnesiac client when it detects
> that the client has suffered a traumatic event.
> 
> Fred
> 
> > -----Original Message-----
> > From: [e-mail] [mailto:[e-mail]]
> > Sent: Wednesday, October 07, 2020 6:55 AM
> > To: Templin (US), Fred L <[e-mail]>
> > Cc: [e-mail]; v6ops list <[e-mail]>; 6man WG <[e-mail]>; dhcwg <[e-mail]>
> > Subject: Re: [dhcwg] [EXTERNAL] Question to DHCPv6 Relay Implementors regarding draft-ietf-dhc-dhcpv6-pd-relay-requirements
> >
> > This message was sent from outside of Boeing. Please do not click links or open attachments unless you recognize the sender and
> > know that the content is safe.
> >
> >
> >
> > > On 7 Oct 2020, at 15:50, Templin (US), Fred L <[e-mail]> wrote:
> > >
> > > We implement DHCPv6 PD on relays. The relay is always co-resident with the
> > > delegating server and behaves according to RFC6221. Are we covered?
> >
> > What's your experience with implementing section 3.5 / R-4?
> >
> > Cheers,
> > Ole
> >
> > >
> > > Thanks - Fred
> > >
> > > From: dhcwg [mailto:[e-mail]] On Behalf Of [e-mail]
> > > Sent: Wednesday, October 07, 2020 3:26 AM
> > > To: v6ops list <[e-mail]>; [e-mail]
> > > Cc: dhcwg <[e-mail]>
> > > Subject: [EXTERNAL] [dhcwg] Question to DHCPv6 Relay Implementors regarding draft-ietf-dhc-dhcpv6-pd-relay-requirements
> > >
> > > This message was sent from outside of Boeing. Please do not click links or open attachments unless you recognize the sender and
> > know that the content is safe.
> > >
> > >
> > > Hi,
> > >
> > > We are currently finishing WGLC for this draft. It describes requirements for a 'DHCPv6 Delegating Relay' - this is a router
> functioning
> > as the L3 edge and DHCPv6 relay (only) with prefix delegation. This is a common deployment scenario, but RFC3633/8415 only really
> > describes PD using a Delegating Router - i.e the L3 edge also functions as a DHCPv6 server with no relay. When the relay and server
> > functions are performed by separate devices a number of problems with how relays behave have
> > > been observed, so this document addresses them.
> > >
> > > During WGLC for this, Ole raised a comment related to one of the routing requirements:
> > >
> > > R-4:    If the relay has learned a route for a delegated prefix via a
> > >            given interface, and receives traffic on this interface with
> > >            a destination address within the delegated prefix (that is
> > >            not an on-link prefix for the relay), then it MUST be
> > >            dropped.  This is to prevent routing loops.  An ICMPv6 Type
> > >            1, Code 6 (Destination Unreachable, reject route to
> > >            destination) error message MAY be sent back to the client.
> > >            The ICMP policy SHOULD be configurable.
> > >
> > > The problem that this is trying to solve is:
> > >
> > > 3.5.  Forwarding Loops between Client and Relay
> > >
> > >    If the client loses information about a prefix that it is delegated
> > >    while the lease entry and associated route is still active in the
> > >    delegating relay, then the relay will forward traffic to the client
> > >    which the client will return to the relay (which is the client's
> > >    default gateway (learnt via an RA).  The loop will continue until
> > >    either the client is successfully reprovisioned via DHCP, or the lease
> > >    ages out in the relay.
> > >
> > > Ole’s comment: "And I would also be happy if we could have some implementors chime in with a "we are happy and able to
> > implement this requirement”.”
> > >
> > >
> > > We would appreciate any feedback on this, especially from anyone with experience implementing DHCPv6 relays with PD.
> > >
> > >
> > > Thanks,
> > > Ian
> > >
> > >
> > > Current draft version: https://datatracker.ietf.org/doc/draft-ietf-dhc-dhcpv6-pd-relay-requirements/
> > >
> > >
> > > _______________________________________________
> > > dhcwg mailing list
> > > [e-mail]
> > > https://www.ietf.org/mailman/listinfo/dhcwg
> 
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