And what about log based replication ?
Lots of banks have chosen Sybase or DB2 for this.
This is an external process which scans the log buffer, queue and sends the modifications to the standby server (like log shipping in MS SQL but in memory).
The standby server is actually available all the time (for reporting).
It's independant on the OS (you can upgrade Windows) and on the database version.
That seems to be very robust and very flexible.
Is someone has had any experiences with this ?