BW Extractors During ECC Upgrade

Question

All, We are moving from 46B to ECC. One of the open questions we have is what needs to be done during the upgrade prepare phase with the extractors from our BW system.
We are using the downtime minimized approach, so the prepare phase will start several days prior to the start of upgrade downtime. Here is the question: We have 50+ delta extractors running that pull data from the ECC system to BW. SAP has told us that during the prepare phase (this is during system uptime) we will need to turn off the extractors and clear the delta queues prior to the prepare phase running. But they are also telling us that we COULD turn them back on after prepare is complete but before the downtime starts but that they do not recommend it.
Any experience with BW extractors and an ECC upgrade? Since we are starting the ECC prepare phase several days prior to the start of downtime for the upgrade, we are trying to determine whether we will be without BW feeds for that entire time or only during the downtime.
Thanks!

Answer 1

> Thanks for the reply. So you see no reason to have
> the extrators off the entire time between when
> RSVBCHK is run during prepare and when it is run
> during the downtime?
No - I don't see it. We used that procedure when we went from 4.6 to 4.7 and it worked - we didn't have any data loss.
> We will have approximately 48 hours between the
> prepare and the start of downtime and obviously the
> business would prefer to have the extracts available
> during this time.
RSVBCHK doesn't just check for the BI deltas but for cancelled update tasks too and some more things.
You must though make sure that nobody creates any more deltas (thus no more production) after you passed RSVBCHK during UPGRADE OR make sure, someone is around at a later point before you shutdown the system and load the data out of the R/3 system. You must make sure that all deltas are loaded before you enter MODPROF_TRANS, if you still have delta there, it will be lost.
Markus