Unofficial Oracle Database Appliance FAQ

Sep 21, 2011 / By Marc Fielding

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I’ve started putting together some information about the Oracle Database Appliance in question-and-answer form. If you have an unanswered question, ask away in the comment section below.

(Update: Oracle has come out with their official FAQ as well)

Why ODA?
ODA offers the benefits of engineered, pre-configured systems for environments too small for Exadata. These benefits include fast deployment, simple configuration, and a tested and certified combination of hardware and software.

What database versions can I use with ODA?
At this point, only Oracle 11.2.0.2 enterprise edition. I’d expect future Oracle versions to run on the ODA as well.

How is the software licensed?
The Oracle database appliance is licensed on a per-processor basis at the same rate as for other platforms. Existing Oracle per-processor licenses can be used with ODA. It’s possible to license a subset of processors, but after the initial sizing, the processor count cannot be decreased, only increased.

What kind of HA (high availability) options exist with ODA?
The ODA hardware is completely redundant internally. ODA can participate in the same HA configurations as other Oracle database servers, including Oracle Data Guard and Oracle GoldenGate.

How is the flash memory used?
ODA comes configured with flash storage in a REDO diskgroup, holding database redo logs

Why should I store redo logs in flash memory
Traditional enterprise storage infrastructure uses battery-backed memory caches to buffer writes, significantly improving commit latency for Oracle databases. Since ODA doesn’t have such a cache, it uses flash memory for this purpose instead. (As of version 11.2.2.4.0, Exadata does this too)

Can the flash memory be used as a read cache?
No; the flash storage is optimized for redo caching only. It uses a different ASM block size through an ODA-specific version of ASM.

Can I hook the ODA up to my SAN?
ODA does not have a fiber HBA card so can’t connect directly to fiber channel fabrics. However, ODA can access SAN disks via IP protocols like iSCSI or NFS, though they have higher overhead than ODA’s own direct-attached disk.

Can I connect multiple ODA units together?
Each ODA device is self-contained, and communicates externally with comparatively slow network access, so you would typically want to separate databases between ODA units. If you’re looking at a larger configuration, consider Exadata instead

Can I store regular files on the ODA’s shared storage?
Yes. Since it has direct-attached disk, ODA can use Oracle’s ASM cluster filesystem (ACFS) filesystems to store regular OS files in ASM, accessible to both system controllers in the ODA.

18 Responses to “Unofficial Oracle Database Appliance FAQ”

  • Robert says:

    Hi Marc,

    Great FAQ. Just wondering where you obtained the details on Named User Licensing. We have received advice that you can only install Processor Licenses, so I am keen to verify that you can utilise Named User licensing based on the number of cores activated.

    Would be great if you can provide a link to some Oracle documentation that verifies this.

    Regards, Rob

  • @Rob: You’re right: the licensing guide (http://download.oracle.com/docs/cd/E22693_01/doc.21/e25375/chapter1.htm) lists licensing as being tied to CPU cores, so you might have trouble with named users. Another interesting tidbit from that chapter: you can reduce the number of licensed cores only once, and subsequent changes must all be increases. So it looks like this licensing metric isn’t designed to temporarily add capacity for a short period of time.

  • JMIZE says:

    Hi Mark,

    Great information here – finding some of these answers is still difficult due to the “newness” of ODA. I am curious on the iscsi point you make. Is that information present in Oracle-provided documentation or internal resources at Oracle? I have heard NFS but have not seen/heard iSCSI information yet.

    Thanks for any info.

    • @JMIZE: there are no specific software certifications for the Oracle database appliance: software is supported in much the same manner as is running an Oracle database on non-Oracle hardware. That having been said, iSCSI is a high-overhead protocol because of the need to encapsulate all data in IP packets, so I’d expect higher latency than the build-in direct-attached storage in the ODA itself.

  • Wilix says:

    Thanks for the info sharing. Since you mentioned about data guard and goldengate as a HA option to ODA, how about database security option? Are they workable when sit in ODA?

    Another question was surrounding my mind is that can data guard or active data guard work between Exadata & ODA? Say Exadata at production and ODA at DR.

    Appreciate for any feedback. Thanks.

    • @Wilix: The Oracle Database Appliance runs standard Oracle 11g software, and can run the Advanced Security option. If you’re using transparent data encryption, you should be able to use the AES-NI crypto offload features in the ODA’s Xeon 5675 to reduce CPU impact of data encryption/decryption. (http://docs.oracle.com/cd/E11882_01/network.112/e10746/whatsnew.htm#ASOAG10115 for more info)

      And yes it’s possible to run data guard and active data guard with an Exadata primary and an ODA standby with a few caveats:
      – Tables compressed with Hybrid Columnar Compression will not be accessible on the ODA until they are rebuilt without HCC using ALTER TABLE MOVE
      – Keep in mind that, unlike Exadata, the processing and direct-attached storage capacity of ODA are not expandable. So you would need to manage database size so that it fits on an ODA standby, and has sufficient spare capacity for rebuilding those HCC-compressed tables if necessary.
      (However you can expand non-direct-attached storage using iSCSI or NFS, but then you’d be losing a lot of the simplicity of the ODA model)

  • Wael Fattal says:

    Can a client license only 2 core and work with the full hardware capacity (24 cores)

    • Hello Wael,

      Think of it this way: if Oracle let you use all 24 CPU cores while only paying for 2, who would pay for the full amount?

      If you license 2 CPU cores, the system will be restricted to using 2 cores only. Unlike other Oracle products where licensing is more or less on the “honour system” backed by audits, in the case of ODA it’s enforced in the system.

      Cheers,

      Marc

  • Simon Haslam says:

    @Wael Just to add a little to Marc’s comment, when running ODA in physical mode the BIOS is used to control the number of cores enabled. I’m not sure 2 total is actually an option anyway (i.e. 1 core on each server) – I *guess* 4 is the minimum (1 core on each processor in each server). You have to wonder how well a 2 node cluster would run on 1 core though for a workload that would justify DB EE, RAC/RON and ODA.

    However if you’re using the new virtual installation of ODA it limits the cores available to the database (in the ODA Base VM) with the OVM hypervisor and you could make use of the remaining cores, e.g. for middleware VMs – I blogged about it here: http://www.veriton.co.uk/roller/fmw/entry/middleware_on_the_oracle_database if you’re interested.

  • Nisha says:

    Hi Marc,
    Is there any recommended document to set up DG for ODA(Rac one node).
    Thanks

  • heart passions says:

    Hi, nice FAQs,
    I need to know how we can allocate the disk size to the database from the physical disk.
    thnaks

  • heart passions says:

    Hi Marc

    Thanks alot for the fast response of the quires, really appreciated.
    The guide looks nice. Thanks for this :) cheers

  • Tomas Olaj says:

    Is there an unsupported way of re-allocate disks from RECO to DATA, as we are not using any of the disks in RECO (we use iSCSI to store RMAN files externaly) ? I have seen a few “HOWTO”s on EXA systems, but no ones for ODA. Oracle Support says it is not possible/supported, and that we need to reconfigure and wipe out the setup (even for an expansion storage). Which is already hard as we are in production.

    Regards,
    Tomas

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