patch: bad ipv6 neighbor solicitation
Li, Qing
qing.li at bluecoat.com
Tue Dec 15 22:01:14 UTC 2009
Thanks for sending me the routing table output.
Actually I believe both your problems are indeed related to the
prefix route.
I was able to reproduce Dennis Glatting's problem, which was due
to one of the prefix entry being off-link.
In your case the prefix route for 2610:28:1800:4001:20e:cff:fe9f:faad
disappeared and is not in the routing table. If you add the route
by hand the problem should go away.
I guess the question is what triggered the prefix route deletion.
-- Qing
> -----Original Message-----
> From: owner-freebsd-stable at freebsd.org [mailto:owner-freebsd-
> stable at freebsd.org] On Behalf Of Li, Qing
> Sent: Tuesday, December 15, 2009 1:46 PM
> To: Tom Pusateri
> Cc: freebsd-net at freebsd.org; freebsd-stable at freebsd.org
> Subject: RE: patch: bad ipv6 neighbor solicitation
>
> Thanks for reporting back. I asked you for a routing table dump
> in my previous email, would you mind emailing it to me privately?
>
> -- Qing
>
>
> > -----Original Message-----
> > From: Tom Pusateri [mailto:pusateri at bangj.com]
> > Sent: Tuesday, December 15, 2009 1:28 PM
> > To: Li, Qing
> > Cc: freebsd-net at freebsd.org; freebsd-stable at freebsd.org
> > Subject: Re: patch: bad ipv6 neighbor solicitation
> >
> > I didn't think this routing patch was related to the "bad neighbor
> > solicitation messages" as suggested in the subject field but I tried
> it
> > anyway. It does not fix my IPv6 problem. I still get "bad neighbor
> > solicitation messages" and freebsd 8 doesn't respond to 4/5 IPv6
> pings.
> >
> > Thanks,
> > Tom
> >
> > On Dec 14, 2009, at 11:53 PM, Li, Qing wrote:
> >
> > > Please find the more proper fix at
> > >
> > > http://people.freebsd.org/~qingli/nd6-patch.diff
> > >
> > > I realized I was slightly off in my previous email after
> > > I spent a bit more time looking through the problem.
> > > Both prefixes are present but one was marked off-link due
> > > to the fact only a single prefix route was installed in
> > > the routing table (non RADIX_MPATH system).
> > >
> > > I evaluated various options to fixing this issue, however,
> > > due to the association between NDPRF_ONLINK and the route
> > > installation, I decided to go with what I have here for
> > > the time being.
> > >
> > > I have verified the fix in my setup. Please apply the
> > > patch and report back.
> > >
> > > Thanks,
> > >
> > > -- Qing
> > >
> > >
> > >> -----Original Message-----
> > >> From: owner-freebsd-net at freebsd.org [mailto:owner-freebsd-
> > >> net at freebsd.org] On Behalf Of Li, Qing
> > >> Sent: Monday, December 14, 2009 3:00 PM
> > >> To: Dennis Glatting; JASSAL Aman
> > >> Cc: freebsd-net at freebsd.org
> > >> Subject: RE: Understanding multiple IPv6 interfaces under 8.0
(fwd)
> > >>
> > >>
> > >> You don't need to perform all that route-foo. I believe the root
> > cause
> > >> of
> > >> this issue may be due to a bit of regression in the IPv6 prefix
> > >> management
> > >> code, and I am in the process of putting together a permanent
fix.
> > >>
> > >> The issue as it stands today, is due to how the prefix was
> inserted
> > in
> > >> the first place. Since bce0 was configured first, the interface
> > >> associated
> > >> with the prefix is bce0. Later the reference count on the prefix
> is
> > >> simply incremented when bce1 configures another IPv6 address of
> the
> > >> same prefix.
> > >>
> > >> When ND6 NS arrives for bce1, due to the interface mismatch of
the
> > >> prefix
> > >> interface against the input interface, the NS packet was
> considered
> > >> invalid and thus dropped.
> > >>
> > >> Again, in case you didn't see my earlier reply, try the temporary
> > hack
> > >> at
> > >> http://people.freebsd.org/~qingli/nd6-ns.diff
> > >>
> > >> until I commit a permanent patch. The problem was easily
> > reproducible
> > >> and
> > >> I have verified with limited unit testing the patch works.
> > >>
> > >> -- Qing
> > >>
> > >>
> > >> -----Original Message-----
> > >> From: owner-freebsd-net at freebsd.org on behalf of Dennis Glatting
> > >> Sent: Mon 12/14/2009 2:03 PM
> > >> To: JASSAL Aman
> > >> Cc: freebsd-net at freebsd.org
> > >> Subject: Re: Understanding multiple IPv6 interfaces under 8.0
(fwd)
> > >>
> > >>
> > >> Thanks. Responses in-line.
> > >>
> > >>
> > >>
> > >> On Mon, 14 Dec 2009, JASSAL Aman wrote:
> > >>
> > >>> Hello Mr.Glatting,
> > >>>
> > >>> Not that I'm an IPv6 genius, but at first sight your problem
> seems
> > > to
> > >> be a
> > >>> route-related. I've put comments in-line.
> > >>>
> > >>>
> > >>> Le Dim 13 d?cembre 2009 22:58, Dennis Glatting a ?crit :
> > >>>>
> > >>>>
> > >>>> Elmer# netstat -rn
> > >>>> Routing tables
> > >>>>
> > >>>>
> > >>>> Internet6:
> > >>>> Destination Gateway
> > >> Flags
> > >>>> Netif Expire
> > >>>> ::/96 ::1
> > > UGRS
> > >>>> lo0 => default fd7c:3f2b:e791:1::1
> > >>>> UGS bce0
> > >>>> ::1 ::1
> UH
> > >>>> lo0 ::ffff:0.0.0.0/96 ::1
> > >> UGRS
> > >>>> lo0 fd7c:3f2b:e791:1::/64 link#1
> > >> U
> > >>>> bce0 fd7c:3f2b:e791:1::ac13:a0a link#1
> > >> UHS
> > >>>> lo0 fd7c:3f2b:e791:1:0:1:ac13:a0a link#2
> > >> UHS
> > >>>> lo0 fe80::/10 ::1
> > >> UGRS
> > >>>> lo0 fe80::%bce0/64 link#1
> > >> U
> > >>>> bce0 fe80::213:72ff:fe60:ac52%bce0 link#1
> > >> UHS
> > >>>> lo0 fe80::%bce1/64 link#2
> > >> U
> > >>>> bce1 fe80::213:72ff:fe60:ac50%bce1 link#2
> > >> UHS
> > >>>> lo0 fe80::%lo0/64 link#3
> > >> U
> > >>>> lo0 fe80::1%lo0 link#3
> > >> UHS
> > >>>> lo0 ff01:1::/32
> > fe80::213:72ff:fe60:ac52%bce0
> > >> U
> > >>>> bce0 ff01:2::/32
> > > fd7c:3f2b:e791:1:0:1:ac13:a0a
> > >> U
> > >>>> bce1 ff01:3::/32 ::1
> > >> U
> > >>>> lo0 ff02::/16 ::1
> > >> UGRS
> > >>>> lo0 ff02::%bce0/32
> > fe80::213:72ff:fe60:ac52%bce0
> > >> U
> > >>>> bce0 ff02::%bce1/32
> > > fd7c:3f2b:e791:1:0:1:ac13:a0a
> > >> U
> > >>>> bce1 ff02::%lo0/32 ::1
> > >> U
> > >>>> lo0
> > >>>>
> > >>>
> > >>> Hmm, the entry for fd7c:3f2b:e791:1:0:1:ac13:a0a looks suspect.
I
> > > was
> > >>> expecting bce1 rather than lo0, I suppose you were as well :) If
> > I'm
> > >> not
> > >>> mistaken, the packets emanating from bce1 go to the loopback
> > >> interface,
> > >>> thus not really going out. You can try specifying the route
> > manually
> > >>> with "route add *your parameters*" or even set it in
/etc/rc.conf
> > so
> > >>> that it's loaded at boot-time. There's no reason why among 2
> > > physical
> > >>> interfaces sharing the same fabric, one can ship packets out and
> > the
> > >>> other can't.
> > >>>
> > >>
> > >> I was wondering about the route however I haven't figured out the
> > > trick
> > >> to
> > >> get what I want. For example:
> > >>
> > >> Elmer# route delete -inet6 fd7c:3f2b:e791:1:0:1:ac13:a0a
> > >> delete host fd7c:3f2b:e791:1:0:1:ac13:a0a
> > >>
> > >> Elmer# route add
> > >> -inet6 fd7c:3f2b:e791:1:0:1:ac13:a0a/64 -iface bce1
> > >> route: writing to routing socket: File exists
> > >> add net fd7c:3f2b:e791:1:0:1:ac13:a0a/64: gateway bce1: route
> > already
> > >> in table
> > >>
> > >> I did delete the lo0 route before I exected the above command.
> Also,
> > I
> > >> haven't been able to specify a higher metric (e.g., -metric 2).
> That
> > > is
> > >> rejected too. However, I can say:
> > >>
> > >> Elmer# route delete -inet6 fd7c:3f2b:e791:1:0:1:ac13:a0a
> > >> delete host fd7c:3f2b:e791:1:0:1:ac13:a0a
> > >>
> > >> Elmer# route add -inet6 fd7c:3f2b:e791:1:0:1:ac13:a0a -iface bce1
> > >> add host fd7c:3f2b:e791:1:0:1:ac13:a0a: gateway bce1
> > >>
> > >> Elmer# netstat -rn
> > >> (snip)
> > >> fd7c:3f2b:e791:1:0:1:ac13:a0a 00:13:72:60:ac:50
> UHS
> > >> bce1
> > >>
> > >> I don't think that is what I want. WHat I think I just said is
> "host
> > > X"
> > >> is
> > >> out that door, rather than route net. If, however, I say Docs is
> out
> > >> that
> > >> door, I get:
> > >>
> > >> Elmer# route add -inet6 docs.dco.penx.com -iface bce1
> > >> add host docs.dco.penx.com: gateway bce1
> > >>
> > >> Elmer# ping6
> > >> docs.penx.com
> > >> PING6(56=40+8+8 bytes) fd7c:3f2b:e791:1:0:1:ac13:a0a -->
> > >> fd7c:3f2b:e791:1::ac13:a15
> > >> ping6: sendmsg: Operation not permitted
> > >> ping6: wrote docs.dco.penx.com 16 chars, ret=-1
> > >>
> > >>
> > >>>>
> > >>>> Elmer's rc.config:
> > >>>>
> > >>>>
> > >>>> ipv6_enable="YES" ipv6_network_interfaces="bce0 bce1"
> > >>>> ipv6_ifconfig_bce0="FD7C:3F2B:E791:0001::0:172.19.10.10
> prefixlen
> > >> 64"
> > >>>> ipv6_ifconfig_bce1="FD7C:3F2B:E791:0001::1:172.19.10.10
> prefixlen
> > > 64
> > >> mtu
> > >>>> 8192"
> > >>>> ipv6_defaultrouter="FD7C:3F2B:E791:0001::1"
> > >>>>
> > >>>
> > >>> Erm... You're using IPv4 addresses encapsulated in IPv6 ? I've
> > never
> > >> used
> > >>> this myself so I can't really comment, and I can't say if there
> > >> aren't any
> > >>> sort of "interferences" with what you're trying to do.
> > >>>
> > >>
> > >> I hope what I am specifying is to use the 32 bit IPv4 address as
> the
> > >> last
> > >> 32 bits of the IPv6 address, at least that is how it works out
> > >> numerically. My numbering scheme for fixed assets is the last 32
> > bits
> > >> of
> > >> the 128 bit IPv6 address is the same as its IPv4 address.
> > >>
> > >>
> > >>>>
> > >>>>
> > >>>> The router (cisco):
> > >>>>
> > >>>>
> > >>>> interface GigabitEthernet0/0 ipv6 address
FD7C:3F2B:E791:1::1/64
> > >> ipv6
> > >>>> enable ipv6 nd prefix FD7C:3F2B:E791:1::/64 (etc)
> > >>>>
> > >>>
> > >>> Just a side-note, I'm not sure if it will be really useful to
you,
> > >> but you
> > >>> could give it a try if you want to. Have you tried using your
> Cisco
> > >> router
> > >>> as a Router Advertisement Daemon ? That way, addresses would be
> > > built
> > >>> automatically and you could see how both interfaces react to
such
> > >>> advertisements.
> > >>>
> > >>> I hope this helps.
> > >>>
> > >>> ------------
> > >>> Aman Jassal
> > >>>
> > >>> Wisdom comes from experience.
> > >>> Experience comes from a lack of wisdom.
> > >>>
> > >>>
> > >> _______________________________________________
> > >> freebsd-net at freebsd.org mailing list
> > >> http://lists.freebsd.org/mailman/listinfo/freebsd-net
> > >> To unsubscribe, send any mail to "freebsd-net-
> > unsubscribe at freebsd.org"
> > >>
> > >> _______________________________________________
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> > unsubscribe at freebsd.org"
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