Comment 6 for bug 423988

Jiri Tyr wrote:
>>> - there should be an utility to check if all backends are in sync and synchronize them if needed.
>>>
>>> This is not really necessary if you are using the multi:// patch.
>> But it is because now if the upload to the second backend fails next
>> time duplicity start it will see that the file have been uploaded
>> because it is available on the firs backend
>
> I see. But this is only for the case of non-full backup. If you do full
> backup, it doesn't matter.

I have got and idea how to do it even if you do the incremental backup:

Before you create new incremental backup, you check if there are the
same timestamps of the last backup on all destinations. If so, you do
the new backup. If not, you check what's the last common backup and you
sync the rest. If there is no common backup you end up with an error.
You should also consider the situation that on one destination is full
backup and on other one is incremental backup. Then you should end up
with an error.

What do you think?