Upgrading ASM to Oracle 11g
Oracle 11g New Features Tips by Burleson
July 8, 2008
Oracle 11g SQL
New Features Tips
When upgrading from Oracle database 10g to 11g,
it comes in very handy to have installed the 10g Oracle software two
times in two different ORACLE_HOME directories, an
ASM_HOME and a DB_HOME. This is the recommended best
practice if ASM is being used because it makes one independent when
it comes to upgrading. The reason why is that it is possible to have
an 11g database use ASM disk groups which are managed by a 10g ASM
instance and vice versa.
Therefore, just those 10g databases can be
upgraded to 11g which are running applications that have already
been certified for 11g and the others can remain on 10g until their
applications are certified as well while still using the same ASM
disk groups as before. In this case, it would be sensible to upgrade
the ASM_HOME to 11g, which would cause downtime for all
instances depending on the ASM instances running from this home.
After this, all database instances, the 10g as
well as the 11g, could use the ASM disk groups managed by the now
upgraded Oracle 11g ASM instance. It would then be possible to
convert the managed disk groups to 11g compatibility as soon as all
databases using them have been upgraded to 11g as well. From this
moment on, all databases could profit from the 11g New Features for
The difference between the relationships of database instances
with ASM instances in 10g and 11g is the format of the messages sent
between each other and the format of the metadata which describe the
disk groups. The format of these messages determines which ASM
features can be used by a database. The format of the metadata
determines which features a disk group can handle. A third factor
which needs to match is the value of the initialization parameter
COMPATIBLE of the DB instance as well the ASM instance. This is
something that cannot be worked around when upgrading the ASM
version in a single instance environment.
This is an
excerpt from the new book
Oracle 11g New Features: Expert Guide to the Important
New Features by John Garmany, Steve Karam, Lutz Hartmann, V. J.
Jain, Brian Carr.
You can buy it direct from the publisher
for 30% off.