Re: push apps failing in Android until you disable IPv6

[Ted Mittelstaedt]

That is correct, Tim

When you define an interface in Cisco IOS as IPv6 enabled but you don't
assign a prefix, all you get is LL assignments from it.  I don't think
that IOS version 12 has any notion of ULA addresses in IPv6.

Keep in mind that I only tested IPv6 assignment, not reachability.
I wanted to see if it was possible to configure the router to
assign just LL and advertise a DG and Android would pick it up.

I wonder if you assign an IPv6 DNS server, LL addressing, and
advertise a DG, would Android ignore RFC 6724 and attempt to reach
the IPv6 DNS servers before attempting to reach the IPv4 DNS servers?

Ted

On 5/9/2016 6:48 AM, Tim Chown wrote:

On 9 May 2016, at 10:17, Tore Anderson  wrote:

* Erik Kline


If this router were to send out an RA advertising itself as a default
router in this configuration that would probably cause the symptoms
you're seeing.  That's why I asked for a sample of any RAs seen on
such a network.  (Such a configuration would of course be broken,
effectively requiring Happy Eyeballs to function at all.)


Assuming the source address selection is implemented in a sane way,
just having a an IPv6 default router doesn't on its own explain the
symptoms described. IPv4 should be preferred due to the Android device's
link-local address not having the same scope as the IPv6 address of the
web site or whatever. See RFC6724 sections 5 and 6, rule 2.

The RA would have to additionally contain a PIO with global scope, as I
understand it. Then you'd certainly get in trouble (disregarding Happy
Eyeballs). Even a ULA PIO could be problematic if Android's source
address selection algorithm isn't updated to RFC6724 defaults. RFC3484
predates ULAs, so it treats them the same as other globally scoped
addresses.


This was one of the reasons for the RFC 6724 update, and would fit the symptoms 
being described were the device using older heuristics, but it sounds like the 
device has only LL and not ULA, right Ted?

Tim

Re: push apps failing in Android until you disable IPv6

[Ted Mittelstaedt]

Michael,

Just about all posters to those threads are end users not system admins 
and just about everything they have posted is sheer speculation.  None

have really tested in a lab.  Most seem concentrated on app settings or
are convinced it's an app bug.

They are reporting the issue on 6.x , 5.x and some earlier than that.
Some of what they are reporting is certainly app setting errors.

It would be useful to ask some of the people posting on those threads
if they have tried turning off wifi on the phone for a day or so
and seeing if the push notifications all started working.  That might
get us some useful data.  If push notices work on their cell carriers
data but not their own wifi network then you can reasonably argue that
there is a problem with their wifi network.   That would be the first
step to getting them to do some logical troubleshooting.

Ted

On 5/10/2016 8:10 AM, Michael Oghia wrote:

Hi everyone,

I am an Android user (but not a developer) and an avid follower of
AndroidPolice.com. AP has been reporting about a similar issue for some
time (see: here
,
here
,
and here
).
The issue concerns Android push notifications for Gmail, and many Nexus
users specifically had raised the issue on the Nexus Help Forums
 as
well as filed multiple bug reports on the Android Issue Tracker
. As you can
read in the third link, it was supposedly fixed in previous builds but
the problem has persisted for some. I don't know if the issue raised in
this thread is the same, but I figured it was prudent to bring it to
your attention.

Since Android Police were the ones who covered it, I also CC'd
Artem Russakovskii, the editor-in-chief. The AP staff may be able to
provide more information in addition to what has been discussed so far.

Best,
-Michael
__

Michael J. Oghia
Istanbul, Turkey
Journalist & editor
2015 ISOC IGF Ambassador
Skype: mikeoghia
Twitter  *|* LinkedIn


On Tue, May 10, 2016 at 4:48 PM, Mikael Abrahamsson mailto:swm...@swm.pp.se>> wrote:

On Tue, 10 May 2016, Erik Kline wrote:

It's really not clear to me what that version of rdisc6 would
print if
it encounters options about which it did not know anything.  A
pcap of
just an RA would be best.  The adb commands I pasted should also
suffice to show what the device thinks it has for DNS, routes,
everything.


The version of rdisc6 included in Ubuntu 14.04 displays recursive
DNS server.

This is also seen in "tcpdump -vvv -n -i eth0 icmp6" and I see it as:

rdnss option (25), length 24 (3):


--
Mikael Abrahamssonemail: swm...@swm.pp.se 

Re: push apps failing in Android until you disable IPv6

[Michael Oghia]

Hi everyone,

I am an Android user (but not a developer) and an avid follower of
AndroidPolice.com. AP has been reporting about a similar issue for some
time (see: here
,
here
,
and here
).
The issue concerns Android push notifications for Gmail, and many Nexus
users specifically had raised the issue on the Nexus Help Forums
 as well
as filed multiple bug reports on the Android Issue Tracker
. As you can
read in the third link, it was supposedly fixed in previous builds but the
problem has persisted for some. I don't know if the issue raised in this
thread is the same, but I figured it was prudent to bring it to your
attention.

Since Android Police were the ones who covered it, I also CC'd
Artem Russakovskii, the editor-in-chief. The AP staff may be able to
provide more information in addition to what has been discussed so far.

Best,
-Michael
__

Michael J. Oghia
Istanbul, Turkey
Journalist & editor
2015 ISOC IGF Ambassador
Skype: mikeoghia
Twitter  *|* LinkedIn


On Tue, May 10, 2016 at 4:48 PM, Mikael Abrahamsson 
wrote:

> On Tue, 10 May 2016, Erik Kline wrote:
>
> It's really not clear to me what that version of rdisc6 would print if
>> it encounters options about which it did not know anything.  A pcap of
>> just an RA would be best.  The adb commands I pasted should also
>> suffice to show what the device thinks it has for DNS, routes,
>> everything.
>>
>
> The version of rdisc6 included in Ubuntu 14.04 displays recursive DNS
> server.
>
> This is also seen in "tcpdump -vvv -n -i eth0 icmp6" and I see it as:
>
> rdnss option (25), length 24 (3):
>
>
> --
> Mikael Abrahamssonemail: swm...@swm.pp.se
>

Re: push apps failing in Android until you disable IPv6

[Mikael Abrahamsson]

On Tue, 10 May 2016, Erik Kline wrote:


It's really not clear to me what that version of rdisc6 would print if
it encounters options about which it did not know anything.  A pcap of
just an RA would be best.  The adb commands I pasted should also
suffice to show what the device thinks it has for DNS, routes,
everything.


The version of rdisc6 included in Ubuntu 14.04 displays recursive DNS 
server.


This is also seen in "tcpdump -vvv -n -i eth0 icmp6" and I see it as:

rdnss option (25), length 24 (3):

--
Mikael Abrahamssonemail: swm...@swm.pp.se

Re: push apps failing in Android until you disable IPv6

[Phil Mayers]

On 10/05/16 14:10, JORDI PALET MARTINEZ wrote:

Understood, thanks !

I just read all the Doze thing :-) I also recall something published
by Lorenzo about power saving in IPv6, etc., however, I still fail to
see if there is no GUA, why Android is affected using only IPv4.


Well, it is probably a bug. Just could be a bug in a lot of places - 
user, kernel, wifi driver, wifi firmware, even wifi hardware. Some of 
those are Google-supplied (but possibly manufacturer modified?) but 
others are IHV-supplied IIUC.


The fact that IPv6 pulls in a lot more multicast and thus potential wifi 
complexity might be related.


It might be interesting to know whether the issue is a failure of e.g. 
WMM, so the notify packets aren't being queued to / reaching the 
handset, or whether they're being send over the air, but the handset 
isn't waking up. Could possibly determine that with a wireshark aircap 
on an affected CPE/handset pair if you know the WPA-PSK.


Does the behaviour change if the device is on charge?

Re: push apps failing in Android until you disable IPv6

[JORDI PALET MARTINEZ]

Understood, thanks !

I just read all the Doze thing :-) I also recall something published by Lorenzo 
about power saving in IPv6, etc., however, I still fail to see if there is no 
GUA, why Android is affected using only IPv4.

Regards,
Jordi








-Mensaje original-
De:  en nombre de 
Phil Mayers 
Responder a: 
Fecha: martes, 10 de mayo de 2016, 15:01
Para: Jordi Palet Martinez , 

Asunto: Re: push apps failing in Android until you disable IPv6

>On 10/05/16 13:57, JORDI PALET MARTINEZ wrote:
>> Hi Phil,
>>
>> Not sure if you have seen the previous message with the rdisc6. Your
>> network may be not having a “broken” CPE.
>
>I did.
>
>You'd asked:
>
>"""
>Right, but how this is affecting IPv4 push notifications ?
>"""
>
>I was trying to convey that the wakeup system is complex, and that the 
>broken v6 might be causing the entire wakeup system to fail, including 
>the v4 bit, and to suggest some (wild guess) reasons as to the cause.
>

Re: push apps failing in Android until you disable IPv6

[JORDI PALET MARTINEZ]

Hi Erik,

The rdisc6 is not providing the RDDNS info ? Is the first time I used it, 
actually trying to get it working on my Mac as well ;-)

I will ask the rest of the info and provide it ASAP.

I know is happening with Android version 4.4 y 5.1 (several vendors, I’ve asked 
for more concrete data).

Regards,
Jordi








-Mensaje original-
De:  en nombre de 
Erik Kline 
Responder a: 
Fecha: martes, 10 de mayo de 2016, 14:57
Para: Jordi Palet Martinez 
CC: IPv6 Ops list , Mikael Abrahamsson 

Asunto: Re: push apps failing in Android until you disable IPv6

>More data, like the device type, the OS version, and whether or not
>these RAs also include RDNSS information would be good.
>
>A bug report, or at the very least the output of:
>
>adb shell dumpsys connectivity
>
>and
>
>adb shell dumpsys connectivity --diag
>
>would help further diagnosis.
>

Re: push apps failing in Android until you disable IPv6

[Phil Mayers]

On 10/05/16 13:57, JORDI PALET MARTINEZ wrote:

Hi Phil,

Not sure if you have seen the previous message with the rdisc6. Your
network may be not having a “broken” CPE.


I did.

You'd asked:

"""
Right, but how this is affecting IPv4 push notifications ?
"""

I was trying to convey that the wakeup system is complex, and that the 
broken v6 might be causing the entire wakeup system to fail, including 
the v4 bit, and to suggest some (wild guess) reasons as to the cause.

Re: push apps failing in Android until you disable IPv6

[JORDI PALET MARTINEZ]

Hi Phil,

Not sure if you have seen the previous message with the rdisc6. Your network 
may be not having a “broken” CPE.

The problem has been detected with several combinations of different CPEs and 
Android phones. At the moment I’ve got only rdisc6 from one CPE, but I’m sure 
others have the same problem (announcing a default route with only link-local), 
that’s why te problem is sorted out disabling IPv6 in the CPE.

It happens immediately the phone is “sleep”, not after a certain time, etc.

I’m sure is not an IPv6 on the upstream network, because there is no IPv6 there 
:-(

Saludos,
Jordi








-Mensaje original-
De:  en nombre de 
Phil Mayers 
Responder a: 
Fecha: martes, 10 de mayo de 2016, 13:58
Para: 
Asunto: Re: push apps failing in Android until you disable IPv6

>On 10/05/16 09:58, JORDI PALET MARTINEZ wrote:
>
>> Right, but how this is affecting IPv4 push notifications ?
>
>A lot of stuff goes on to make this work. I'm not an expert on the topic 
>of mobile powersaving, but at minimum:
>
>  * The wireless endpints have to be doing WMM (I think) to queue the 
>packets to the endpoint while the client wifi stack is not powered up.
>
>  * The wifi stack on the client endpoint has to be waking periodically 
>and receiving the queued packets.
>
>  * The wifi stack also has to filter the packets to get only the ones 
>which should wake the CPU, and then wake the CPU and deliver them.
>
>  * There is also the Android-specifc Doze state, which suppresses 
>app/network wakes entirely for progressively longer-spaced check periods:
>
>https://developer.android.com/training/monitoring-device-state/doze-standby.html
>
>This is all network, OS, firmware and hardware-revision dependent, and 
>will vary radically from device model to device model (the variety of 
>android devices being a curse as well as a blessing from this PoV ;o)
>
>I've seen problems with this before on an entirely v4-only network with 
>a very early release of Android on Nexus 4 - my debugging showed the 
>problem was likely with the wake filter, and the next release of Android 
>resolved it.
>
>It's theoretically possible that the issue is on the upstream network, 
>with a failure to do WMM in the presence of IPv6. Or perhaps the 
>presence of a certain v6 config causes the device to fail to process the 
>network traffic at the client end.
>
>Or it's an instance of the doze state, which is behaving differently on 
>an IPv6 network for some reason.
>
>FWIW, my Nexus 5 has no such problems on both v4-only and dualstack 
>networks, so I think you're likely seeing some combo of device- and 
>network-specific behaviour.
>
>When customers report these problems, how long has the device been 
>asleep? Is it possible it's dozing?
>
>IMO you'll need to get hands on a device and network combo that 
>demonstrates the problem to get anywhere; there's just not enough info 
>here to determine the cause, only to guess about the range of possible 
>causes.
>
>Regards,
>Phil
>

Re: push apps failing in Android until you disable IPv6

[JORDI PALET MARTINEZ]

Yes, they work in mobile only.

And they also work if you disable IPv6 in the router, so clearly I believe is 
related to the “wrong” announcement for the default gateway by the router not 
having a GUA, but I guess if there is only a link-local, the Android should not 
“try” anything with which impacts in IPv4 ?

Saludos,
Jordi









-Mensaje original-
De:  en nombre de 
Mikael Abrahamsson 
Organización: People's Front Against WWW
Responder a: 
Fecha: martes, 10 de mayo de 2016, 14:08
Para: Jordi Palet Martinez 
CC: , 
Asunto: Re: push apps failing in Android until you disable IPv6

>On Tue, 10 May 2016, JORDI PALET MARTINEZ wrote:
>
>> But that will not explain why those notifications stop working once the 
>> devices is sleeping, and work again once you unlock the screen ?
>
>Do notifications work when the device is on mobile only? Without wifi 
>turned on at all?
>
>I don't remember the details but I seem to remember I've seen devices that 
>will turn off their wifi when they go to low power mode, and only keep 
>mobile data up.
>
>-- 
>Mikael Abrahamssonemail: swm...@swm.pp.se
>

Re: push apps failing in Android until you disable IPv6

[Mikael Abrahamsson]

On Tue, 10 May 2016, JORDI PALET MARTINEZ wrote:

But that will not explain why those notifications stop working once the 
devices is sleeping, and work again once you unlock the screen ?


Do notifications work when the device is on mobile only? Without wifi 
turned on at all?


I don't remember the details but I seem to remember I've seen devices that 
will turn off their wifi when they go to low power mode, and only keep 
mobile data up.


--
Mikael Abrahamssonemail: swm...@swm.pp.se

Re: push apps failing in Android until you disable IPv6

[Phil Mayers]

On 10/05/16 09:58, JORDI PALET MARTINEZ wrote:


Right, but how this is affecting IPv4 push notifications ?


A lot of stuff goes on to make this work. I'm not an expert on the topic 
of mobile powersaving, but at minimum:


 * The wireless endpints have to be doing WMM (I think) to queue the 
packets to the endpoint while the client wifi stack is not powered up.


 * The wifi stack on the client endpoint has to be waking periodically 
and receiving the queued packets.


 * The wifi stack also has to filter the packets to get only the ones 
which should wake the CPU, and then wake the CPU and deliver them.


 * There is also the Android-specifc Doze state, which suppresses 
app/network wakes entirely for progressively longer-spaced check periods:


https://developer.android.com/training/monitoring-device-state/doze-standby.html

This is all network, OS, firmware and hardware-revision dependent, and 
will vary radically from device model to device model (the variety of 
android devices being a curse as well as a blessing from this PoV ;o)


I've seen problems with this before on an entirely v4-only network with 
a very early release of Android on Nexus 4 - my debugging showed the 
problem was likely with the wake filter, and the next release of Android 
resolved it.


It's theoretically possible that the issue is on the upstream network, 
with a failure to do WMM in the presence of IPv6. Or perhaps the 
presence of a certain v6 config causes the device to fail to process the 
network traffic at the client end.


Or it's an instance of the doze state, which is behaving differently on 
an IPv6 network for some reason.


FWIW, my Nexus 5 has no such problems on both v4-only and dualstack 
networks, so I think you're likely seeing some combo of device- and 
network-specific behaviour.


When customers report these problems, how long has the device been 
asleep? Is it possible it's dozing?


IMO you'll need to get hands on a device and network combo that 
demonstrates the problem to get anywhere; there's just not enough info 
here to determine the cause, only to guess about the range of possible 
causes.


Regards,
Phil

Re: push apps failing in Android until you disable IPv6

[JORDI PALET MARTINEZ]

But that will not explain why those notifications stop working once the devices 
is sleeping, and work again once you unlock the screen ?

For example, you’re using your phone at our home. No IPv6, even if the router 
is announcing a default route having no GUA. Push notifications work.

At this point, is clear that the pull connection was done using IPv4.


Then you let the phone, so it comes to sleep mode, and notifications stop 
working until you wakeup the phone.

As said, in the same scenario, iOS devices are working.

Saludos,
Jordi








-Mensaje original-
De:  en nombre de 
Trevor Warwick 
Responder a: 
Fecha: martes, 10 de mayo de 2016, 12:45
Para: Jordi Palet Martinez 
CC: 
Asunto: Re: push apps failing in Android until you disable IPv6

>I think Push notifications are sent over a "Pull" connection (i.e. one that's 
>initiated by the android device to a central server). So if there is some 
>issue with creating outgoing connections in this scenario, that would cause 
>the problem you've seen.
>
>
>On 10 May 2016 at 09:58, JORDI PALET MARTINEZ  
>wrote:
>
>(Copied back to the list, as the list filtered the original message with the 
>screen capture attachment)
>
>For the info of the list. This is what the rdisc6 provided:
>
>Hop Limit:  64 (0x40)
>Stateful address cons.: No
>Stateful other cons.:   Yes
>Router preference:  medium
>Router lifetime:1800 (0x0708) seconds
>Reachable time: unspecified (0x)
>Retransmit time:unspecified (0x)
>
> MTU:   1472 bytes (valid)
> Source link-layer address: 2C:CF:58:E5:7C:C0
> From fe80::1
>
>Right, but how this is affecting IPv4 push notifications ?
>
>My understanding is that the servers doing the “push”, as the WAN link has not 
>got IPv6, are doing the push with IPv4.
>
>I could understand that Android may be slower to react to dual-stack traffic 
>because there is a default route announced by the router with no GUA, but 
>getting the push ?
>
>By the way, anyone got rdisc6 working in Mac OS X El Capitan ?
>
>Regards,
>Jordi
>
>
>
>
>
>
>
>
>
>-Mensaje original-
>De: Erik Kline 
>Responder a: 
>Fecha: martes, 10 de mayo de 2016, 4:41
>Para: Jordi Palet Martinez 
>CC: Lorenzo Colitti 
>Asunto: Re: push apps failing in Android until you disable IPv6
>
>>Uh...non-zero router lifetime means it's announcing a default route.
>>That seems unwise.
>>
>>On 10 May 2016 at 02:49, JORDI PALET MARTINEZ
>> wrote:
>>> Just got a “screen” capture from one of those situations (rdisc6).
>>>
>>> Hopefully is useful ! They made it from a virtual machine in the same 
>>> network as the Androids have the problema, having the VMware interfaces in 
>>> bridge mode.
>>>
>>> Saludos,
>>> Jordi
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> -Mensaje original-
>>> De:  en 
>>> nombre de Erik Kline 
>>> Responder a: 
>>> Fecha: lunes, 9 de mayo de 2016, 10:59
>>> Para: Jordi Palet Martinez 
>>> CC: IPv6 Ops list , Lorenzo Colitti 
>>> 
>>> Asunto: Re: push apps failing in Android until you disable IPv6
>>>
If this router were to send out an RA advertising itself as a default
router in this configuration that would probably cause the symptoms
you're seeing.  That's why I asked for a sample of any RAs seen on
such a network.  (Such a configuration would of course be broken,
effectively requiring Happy Eyeballs to function at all.)

On 9 May 2016 at 17:52, JORDI PALET MARTINEZ  
wrote:
> Hi Lorenzo,
>
> I don’t have an Android, so I can’t try myself, unfortunately, so I’m 
> just replicating what several folks told me in a training (people from 
> different ISPs, not just one).
>
> I’ve asked already a few days ago for more info, but still didn’t got it. 
> I also asked to open a bug report as Erik suggested as well as the rdisc6 
> from the same LAN.
>
> Let me try to write it down again the issue:
>
> 1) ISP NOT providing IPv6, but CPE supports IPv6, which can be seen in 
> the router configs and the routers has link local, and you can ping with 
> link local to the router in the LAN. Clearly, router has not GUA.
>
> 2) iPhone working fine.
>
> 3) Android fails to receive IPv4 push from whatsapp, Facebook, others, 
> when screen is off.
>
> 4) Disabling IPv6 in the router the problem disappears.
>
> 5) Complains to ISPs are responded with “disable IPv6 in the router”, is 
> not useful at all :-(
>
> I can provide links to web pages from at least one “big” ISP, where they 
> talk about this, but is in Spanish …
>
> I will ping right now again for more info and come back asap.
>
> Thanks !
>
> Regards,
> Jordi
>
>
>
>
>
>
>
>
>
> -Mensaje original-
> De:  en 
> nombre de Lorenzo Colitti 
> Responder a: 
> Fecha: lunes, 9 de mayo de 2016, 10:41
> Par

Re: push apps failing in Android until you disable IPv6

[Trevor Warwick]

I think Push notifications are sent over a "Pull" connection (i.e. one
that's initiated by the android device to a central server). So if there is
some issue with creating outgoing connections in this scenario, that would
cause the problem you've seen.


On 10 May 2016 at 09:58, JORDI PALET MARTINEZ 
wrote:

> (Copied back to the list, as the list filtered the original message with
> the screen capture attachment)
>
> For the info of the list. This is what the rdisc6 provided:
>
> Hop Limit:  64 (0x40)
> Stateful address cons.: No
> Stateful other cons.:   Yes
> Router preference:  medium
> Router lifetime:1800 (0x0708) seconds
> Reachable time: unspecified (0x)
> Retransmit time:unspecified (0x)
>
>  MTU:   1472 bytes (valid)
>  Source link-layer address: 2C:CF:58:E5:7C:C0
>  From fe80::1
>
> Right, but how this is affecting IPv4 push notifications ?
>
> My understanding is that the servers doing the “push”, as the WAN link has
> not got IPv6, are doing the push with IPv4.
>
> I could understand that Android may be slower to react to dual-stack
> traffic because there is a default route announced by the router with no
> GUA, but getting the push ?
>
> By the way, anyone got rdisc6 working in Mac OS X El Capitan ?
>
> Regards,
> Jordi
>
>
>
>
>
>
>
>
>
> -Mensaje original-
> De: Erik Kline 
> Responder a: 
> Fecha: martes, 10 de mayo de 2016, 4:41
> Para: Jordi Palet Martinez 
> CC: Lorenzo Colitti 
> Asunto: Re: push apps failing in Android until you disable IPv6
>
> >Uh...non-zero router lifetime means it's announcing a default route.
> >That seems unwise.
> >
> >On 10 May 2016 at 02:49, JORDI PALET MARTINEZ
> > wrote:
> >> Just got a “screen” capture from one of those situations (rdisc6).
> >>
> >> Hopefully is useful ! They made it from a virtual machine in the same
> network as the Androids have the problema, having the VMware interfaces in
> bridge mode.
> >>
> >> Saludos,
> >> Jordi
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >> -Mensaje original-
> >> De:  en
> nombre de Erik Kline 
> >> Responder a: 
> >> Fecha: lunes, 9 de mayo de 2016, 10:59
> >> Para: Jordi Palet Martinez 
> >> CC: IPv6 Ops list , Lorenzo Colitti <
> lore...@google.com>
> >> Asunto: Re: push apps failing in Android until you disable IPv6
> >>
> >>>If this router were to send out an RA advertising itself as a default
> >>>router in this configuration that would probably cause the symptoms
> >>>you're seeing.  That's why I asked for a sample of any RAs seen on
> >>>such a network.  (Such a configuration would of course be broken,
> >>>effectively requiring Happy Eyeballs to function at all.)
> >>>
> >>>On 9 May 2016 at 17:52, JORDI PALET MARTINEZ <
> jordi.pa...@consulintel.es> wrote:
>  Hi Lorenzo,
> 
>  I don’t have an Android, so I can’t try myself, unfortunately, so I’m
> just replicating what several folks told me in a training (people from
> different ISPs, not just one).
> 
>  I’ve asked already a few days ago for more info, but still didn’t got
> it. I also asked to open a bug report as Erik suggested as well as the
> rdisc6 from the same LAN.
> 
>  Let me try to write it down again the issue:
> 
>  1) ISP NOT providing IPv6, but CPE supports IPv6, which can be seen
> in the router configs and the routers has link local, and you can ping with
> link local to the router in the LAN. Clearly, router has not GUA.
> 
>  2) iPhone working fine.
> 
>  3) Android fails to receive IPv4 push from whatsapp, Facebook,
> others, when screen is off.
> 
>  4) Disabling IPv6 in the router the problem disappears.
> 
>  5) Complains to ISPs are responded with “disable IPv6 in the router”,
> is not useful at all :-(
> 
>  I can provide links to web pages from at least one “big” ISP, where
> they talk about this, but is in Spanish …
> 
>  I will ping right now again for more info and come back asap.
> 
>  Thanks !
> 
>  Regards,
>  Jordi
> 
> 
> 
> 
> 
> 
> 
> 
> 
>  -Mensaje original-
>  De: 
> en nombre de Lorenzo Colitti 
>  Responder a: 
>  Fecha: lunes, 9 de mayo de 2016, 10:41
>  Para: Jordi Palet Martinez 
>  CC: IPv6 Ops list 
>  Asunto: Re: push apps failing in Android until you disable IPv6
> 
> >Jordi,
> >from your report it's not clear what the problem is. You say that the
> problem disappears when IPv6 is disabled on the router, but then you say
> that it also happens on an IPv4-only network. How can those statements both
> be true?
> >
> >It's not usually possible to disable IPv6 on an Android device unless
> the device is rooted, which usually involves installing a non-stock build
> which may behave differently.
> >
> >Also, please clarify what device you're talking about. Stock Android
> should not have this problem, but

Re: push apps failing in Android until you disable IPv6

[JORDI PALET MARTINEZ]

(Copied back to the list, as the list filtered the original message with the 
screen capture attachment)

For the info of the list. This is what the rdisc6 provided:

Hop Limit:  64 (0x40)
Stateful address cons.: No
Stateful other cons.:   Yes
Router preference:  medium
Router lifetime:1800 (0x0708) seconds
Reachable time: unspecified (0x)
Retransmit time:unspecified (0x)

 MTU:   1472 bytes (valid)
 Source link-layer address: 2C:CF:58:E5:7C:C0
 From fe80::1

Right, but how this is affecting IPv4 push notifications ?

My understanding is that the servers doing the “push”, as the WAN link has not 
got IPv6, are doing the push with IPv4.

I could understand that Android may be slower to react to dual-stack traffic 
because there is a default route announced by the router with no GUA, but 
getting the push ?

By the way, anyone got rdisc6 working in Mac OS X El Capitan ?

Regards,
Jordi









-Mensaje original-
De: Erik Kline 
Responder a: 
Fecha: martes, 10 de mayo de 2016, 4:41
Para: Jordi Palet Martinez 
CC: Lorenzo Colitti 
Asunto: Re: push apps failing in Android until you disable IPv6

>Uh...non-zero router lifetime means it's announcing a default route.
>That seems unwise.
>
>On 10 May 2016 at 02:49, JORDI PALET MARTINEZ
> wrote:
>> Just got a “screen” capture from one of those situations (rdisc6).
>>
>> Hopefully is useful ! They made it from a virtual machine in the same 
>> network as the Androids have the problema, having the VMware interfaces in 
>> bridge mode.
>>
>> Saludos,
>> Jordi
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> -Mensaje original-
>> De:  en nombre 
>> de Erik Kline 
>> Responder a: 
>> Fecha: lunes, 9 de mayo de 2016, 10:59
>> Para: Jordi Palet Martinez 
>> CC: IPv6 Ops list , Lorenzo Colitti 
>> 
>> Asunto: Re: push apps failing in Android until you disable IPv6
>>
>>>If this router were to send out an RA advertising itself as a default
>>>router in this configuration that would probably cause the symptoms
>>>you're seeing.  That's why I asked for a sample of any RAs seen on
>>>such a network.  (Such a configuration would of course be broken,
>>>effectively requiring Happy Eyeballs to function at all.)
>>>
>>>On 9 May 2016 at 17:52, JORDI PALET MARTINEZ  
>>>wrote:
 Hi Lorenzo,

 I don’t have an Android, so I can’t try myself, unfortunately, so I’m just 
 replicating what several folks told me in a training (people from 
 different ISPs, not just one).

 I’ve asked already a few days ago for more info, but still didn’t got it. 
 I also asked to open a bug report as Erik suggested as well as the rdisc6 
 from the same LAN.

 Let me try to write it down again the issue:

 1) ISP NOT providing IPv6, but CPE supports IPv6, which can be seen in the 
 router configs and the routers has link local, and you can ping with link 
 local to the router in the LAN. Clearly, router has not GUA.

 2) iPhone working fine.

 3) Android fails to receive IPv4 push from whatsapp, Facebook, others, 
 when screen is off.

 4) Disabling IPv6 in the router the problem disappears.

 5) Complains to ISPs are responded with “disable IPv6 in the router”, is 
 not useful at all :-(

 I can provide links to web pages from at least one “big” ISP, where they 
 talk about this, but is in Spanish …

 I will ping right now again for more info and come back asap.

 Thanks !

 Regards,
 Jordi









 -Mensaje original-
 De:  en 
 nombre de Lorenzo Colitti 
 Responder a: 
 Fecha: lunes, 9 de mayo de 2016, 10:41
 Para: Jordi Palet Martinez 
 CC: IPv6 Ops list 
 Asunto: Re: push apps failing in Android until you disable IPv6

>Jordi,
>from your report it's not clear what the problem is. You say that the 
>problem disappears when IPv6 is disabled on the router, but then you say 
>that it also happens on an IPv4-only network. How can those statements 
>both be true?
>
>It's not usually possible to disable IPv6 on an Android device unless the 
>device is rooted, which usually involves installing a non-stock build 
>which may behave differently.
>
>Also, please clarify what device you're talking about. Stock Android 
>should not have this problem, but some OEMs are known to drop IPv6 packets 
>when the screen is off.
>
>Cheers,
>Lorenzo
>
>On Sat, Apr 30, 2016 at 9:03 PM, JORDI PALET MARTINEZ 
> wrote:
>
>Hi,
>
>I’m not an Android user, but while doing and IPv6 training, many folks in 
>the meeting room told me that they needed to disable IPv6 in the 
>router/Android devices, otherwise they aren’t getting the notifications 
>from WhatsApp, Facebook, and many other apps.
>
>We have tried disabling energy