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Unable to set appliance.mode=TRUE for DBFS diskgroup after Storage Expansion (Doc ID 2671335.1)

Last updated on JULY 27, 2020

Applies to:

Oracle Exadata Storage Server Software - Version and later
Information in this document applies to any platform.


This note applicable for the case where customer added addtional storage cell servers to the existing Rack.

After new cells are configured and added back to ASM, you cannot able to set "appliance.mode=TRUE"  'only' to DBFS diskgroup.

We are able to set this DATA and RECO diskgroups without any issues.


// ASM_alert.log

SQL> alter diskgroup DBFS set attribute 'appliance.mode'='true'
Mon Oct 07 08:24:41 2019
Errors in file
ORA-15414: Appliance mode requires at least 3 failure groups and either 10 or 12 disks in all failure groups.
Mon Oct 07 08:24:42 2019


All the below conditions are met to enable APPLIANCE MODE


To enable APPLIANCE MODE on disk groups should meet the following requirements:

1. The Oracle ASM disk group attribute compatible.asm is set to release, or or later.
2. The cell.smart_scan_capable attribute is set to TRUE.
3. All disks in the disk group are the same type, such that all disks are hard disks or all disks are flash disks.
4. All disks in the disk group are the same size.
5. All failure groups in the disk group have an equal number of disks:
6. For eighth rack configurations, all failure groups have 4 disks, or all failure groups have 6 disks.
7. For all other rack configurations, all failure groups have 10 disks, or all failure groups have 12 disks.
8. There are at least 3 failure groups in the disk group.
9. No disk in the disk group is offline.



 Additional storage cells are added to the Rack or Customer opted Storage expansion rack


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