1234181 - Copying a profile breaks Sync/FxA's device concept

Status: RESOLVED DUPLICATE of bug 1419505

(Firefox :: Sync, defect, P3)

Description

[stefan.mueller.83]

User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:42.0) Gecko/20100101 Firefox/42.0
Build ID: 20151029151421

Steps to reproduce:

Using the same Firefox Sync profile on two different desktop machines in my home network but the have different Sycn names
My work PC and Android phone are connected to same sync account too.


Actual results:

When I open "synced tabs" is shows me only the tabs from the home firefox desktop what was synced last. 
What is going wrong? 


Expected results:

See both home PC on synced tabs

Comment 1

[Mark Hammond [:markh] [:mhammond]]

(In reply to stefan.mueller.83 from comment #0)
> Using the same Firefox Sync profile on two different desktop machines in my
> home network but the have different Sycn names

Can you please explain this setup some more? I'm not sure what it means to use the same profile on 2 different machines, and what them having 2 different Sync names means (other than them using a different Sync account, which would obviously mean they don't share tabs)

Comment 2

[stefan.mueller.83]

here we go:

I have only one account at Firefox Sync: [e-mail]

2x PC at home running Firefox Desktop and each is connected to Sync via [e-mail]
  Each one has its dedicated device name (Firefox preferences -> sync -> device name): PC1 and PC2
  Both PCs are connected to the same LAN. PC1: 192.168.0.10, PC2: 192.168.0.11

1x Android Phone running Firefox for Android, connected to Sync via [e-mail] 

1x PC at work running Firefox Desktop and is connected to Sync via [e-mail]; device name: PC work


Result:
I see only either PC1 or PC2 listed on "tabs from other devices", when I use

Comment 3

[stefan.mueller.83]

here we go:

I have only one account at Firefox Sync: [e-mail]

2x PC at home running Firefox Desktop and each is connected to Sync via [e-mail]
  Each one has its dedicated device name (Firefox preferences -> sync -> device name): PC1 and PC2
  Both PCs are connected to the same LAN. PC1: 192.168.0.10, PC2: 192.168.0.11

1x Android Phone running Firefox for Android, connected to Sync via [e-mail] 

1x PC at work running Firefox Desktop and is connected to Sync via [e-mail]; device name: PC work (not at home)


Result:
I see only either PC1 or PC2 listed on "tabs from other devices", when I use PCwork. In addition I can send tabs from Firefox Android only to either PC1 or PC2, depending which one was synced last.

Comment 4

[Mark Hammond [:markh] [:mhammond]]

Can you please open about:config and check what the preference "services.sync.client.GUID" is on PC1 and PC2? I'm particularly interested to know if they are the same.

Comment 5

[stefan.mueller.83]

they both the same: services.sync.client.GUID;ohtSmBE_wCNp

Comment 6

[Mark Hammond [:markh] [:mhammond]]

(In reply to stefan.mueller.83 from comment #5)
> they both the same: services.sync.client.GUID;ohtSmBE_wCNp

Awesome, thanks - please "reset" one of them and restart Firefox - you should find it automatically gets a new one and things will work. I'll turn this bug into some way of doing a better job here - it also applies to new work we are doing.

Comment 7

[stefan.mueller.83]

problem solved 
thx

Comment 8

[Ryan Kelly [:rfkelly]]

> I'll turn this bug into some way of doing a better job here

Some thoughts on how FxA could do a better job of this in https://github.com/mozilla/fxa-auth-server/issues/1077

The same concept could in theory be applied inside the sync client record, but it'd be more work because the server can't help coerce clients into the correct state.

Comment 9

[Mark Hammond [:markh] [:mhammond]]

(In reply to Ryan Kelly [:rfkelly] from comment #8)
> Some thoughts on how FxA could do a better job of this in
> https://github.com/mozilla/fxa-auth-server/issues/1077
> 
> The same concept could in theory be applied inside the sync client record,
> but it'd be more work because the server can't help coerce clients into the
> correct state.

A "fingerprint" based on hardware and profile location would make sense for handling this "a profile was copied on disk" case (which is subtly different than the above discussion). Taking this further, if we can calculate such a fingerprint reliably, then there seems to be a case for using this as the sync client ID rather than generating a GUID. On the third hand, what do we want to do in the case when the profile is *moved* rather than copied and where the user's expectation is that the profile is identical (ie, the user does not expect a new device to appear)? It's the same basic problem that (eg) VMWare has when it asks you whether you copied or moved the VM instance and hopes you answer the question correctly (else you may end up with duplicate mac addresses, etc). It's subtle and tricky.

Comment 12

[Mark Hammond [:markh] [:mhammond]]

In bug 1365263, rfk writes:

This will need to be driven by client developers, but I want to flag some related discussion on the server-side of FxA that could be relevant:

  https://github.com/mozilla/fxa-auth-server/issues/1077

Comment 13

[Lina Butler [:lina]]

Ed is working on this over in bug 1419505, and started a discussion on firefox-dev@ for detecting copied profiles: https://mail.mozilla.org/pipermail/firefox-dev/2018-March/006155.html