Hi You can create two disk groups, data and fra and place one member in each disk group Regarding a ew disk groups per DB. I only do that when I have to snapshot the disks, seperate each DB in their own disk groups otherwise just use a couple of disk groups. Regards On Tue, Dec 16, 2014 at 4:17 PM, Hameed, Amir <Amir.Hameed@xxxxxxxxx> wrote: > > Hi folks, > > I am in the process of implementing ASM for the first time. I have a few > questions that I would like to ask regarding ASM best practices for both > single instance and RAC databases. The Grid/ASM version is 12.1.0.2: > > · Redo log file placement – In the non-ASM world, I am used to > using two groups for redo logs on multiple mount points with multiple log > members in each group. How does this change in ASM? For an > externally-managed ASM disk group, should there be multiple ASM redo disk > groups with each hosting a redo log group or should one ASM redo disk group > with multiple members be sufficient? > > · Managing multiple databases – In the non-ASM world, we allocate > a separate set of mount points for each database that we set up. This > isolates an environment at the storage level and also enables us to take > storage-based snapshots of a database file systems for backup. Restore is > also simple and quick where we restore from the online snaps. What is the > best approach to manage multiple databases in ASM? Should each DB have its > own set of ASM disk groups or should all databases be placed in the same > set of disk groups? For example, for databases with SIDs ABCD, MNOP & WXYZ: > > o Should there be only one set of ASM disk group (DATA, REDO, RECO, > etc.) for all of the above databases OR > > o Should ABCD be in its own set of disk group (DATA_ABCD, REDO_ABCD, > RECO_ABCO), WXYZ be in its set of disk group (DATA_WXYZ, REDO_ WXYZ, RECO_ > WXYZ), etc.? This model seems to give more flexibility in terms of retiring > an environment where a DG could just be dropped and a new one created when > setting up a new environment, either via cloning or creating one from > scratch. > > · AU and stripe sizes – For an Oracle E-Business Suite type > system, which is hybrid in nature, should the AU size be 1M for the DATA > and REDO groups? Should the stripe size be 1M and 128k for DATA and REDO > groups respectively? > > > > Any feedback will be appreciated. > > > > Thanks, > > Amir >