Database as a Service: Glad that you asked these!

By Sudip Datta

Thanks for visiting my earlier blog post on the new Database as a Service (DBaaS) features which got released in Enterprise Manager 12cR2 Plugin Update 1.

Our first public webcast on DBaaS since the release was pretty well attended with peak attendance going well over our expectation. I wish we had more time to handle the technical Q&A, but since we didn't, let me use the blogosphere to answer some of the questions that were asked. I am repeating some of the questions that we answered during the webcast, because they warrant details beyond what the duration permitted.

Kevin from the audience asked "What's the difference between a regular provisioning and DbaaS?" Sometimes the apparently obvious ones are the most difficult to answer. The recently released whitepaper covers the regular/traditional provisioning versus DBaaS in detail. Long story cut short, in a traditional provisioning model, IT (usually a DBA) uses scripts and tools to provision databases on behalf of end users. In DBaaS IT's role changes and the DBA simply creates a service delivery platform for end users to provision databases on demand as and when they need them. And that too, with minimal inputs ! Here's how the process unfolds:

• The DBA pools together a bunch of server resources that can host databases or a bunch of databases that can host schema and creates a Self-Service zone.
• The DBA creates a gold image and provisioning procedure and expresses that as a service template
• As a result, the end users do not have to deal with the intricacies of the provisioning process. They input a couple of very simple things like the service template and the zone and everything else happens under the hood. The provisioning process, the physicality of the database, etc are completely abstracted out.
• And finally, because DbaaS deals with shared resource utilization and self-service automation, a DBaaS is usually complemented by quota, retirement and chargeback. 

The following picture can make it clear.

In terms of licensing, for a traditional administrator driven database provisioning, you need the Database Lifecycle Management Pack.  If you want to enable DBaaS on top of it, simply add the Cloud Management Pack for Database. 

I will combine the next two questions. Alfred asked, "Is RAC a requirement?" (the short answer for which is "No") while Jud asked, "Is the schema-level provisioning supported in an environment where the target DBs are running in VMs?" First of all, in our DBaaS solution we support multiple models, as shown below.

In the dedicated database model, the database can run on a pool of servers or a pool of cluster. So both single instance and RAC are supported. Similarly, in the dedicated schema (Schema as a Service) model, it can run on single instance or RAC, which can in turn be hosted on physical servers or VMs. Enterprise Manager treats both physical servers and VMs as hosts and as long as the hosts have the agent installed, they can participate in DBaaS. Bottomline is that as we move from IaaS and offer these higher order services, the underlying infrastructure becomes irrelevant. This should also satisfy Steve, who queried "As the technology matures is there an attempt by Oracle to provide ODA vs EXADATA as the foundation of the dbaas to lower the cost?". The answer is YES. But, why wait?  DBaaS is supported on Exa and ODA platforms TODAY. In fact, HDFC Bank in India is running DBaaS on Exadata. You can read about them in the latest Oracle Magazine.

Another interesting question came from Yuri. He asked, "Is there an option to disable startup/shutdown for the self-service users?" It can be answered in multiple ways. First of all, in Schema as a Service or dedicated schema model, the end user cannot control the database instance state because it houses database services (schemas) owned by others too. So this may be a good model for enterprises trying to limit what end users can do at the database instance level.  However, in a dedicated database model, the Enterprise Manager out-of-box self-service console allows the end user to perform operations like startup and shutdown on the database instance. In general, if you want to create your tailored own self-service console with a limited set of operations exposed in the self-service interface, using the APIs may be the way to go. Enterprise Manager 12c also supports RESTFul APIs for self-service operations and hence a limited set of capabilities may be exposed. Check this technical presentation for the supported APIs.

Gordon's question precisely brings out the value of the Enterprise Manager 12c offering. He asked, "How do the services in the cloud get added to Cloud Control monitoring and alerting?" Ever since Amazon became the poster child of public IaaS, enterprises tried emulating their model within the data centers. What most people ignore or forget is that there is a life of the resources in a cloud beyond the provisioning process. Initial provisioning is just the beginning of that lifecycle. In Amazon's case, the management and monitoring of resources is the headache of Amazon's IT staff and consumers are oblivious to the time and effort it takes for them to manage the resources. In a private cloud scenario, one does not have that luxury. Once the database gets provisioned, it needs to monitored for performance, compliance and configuration drifts by company's own  IT staff. In Enterprise Manager 12c, the agent is deployed on the hosts that constitute the pool making the databases automatically managed without any additional work. It comprehensively manages the entire lifecycle and both adminsitrators and self-service users have tailored views of the databases. Well, this also gives me an opportunity to address a question by a participant who alluded to a 3rd party tool exclusively for database provisioning purposes. First of all, as I mentioned during the webcast, Enterprise Manager 12c is the only tool that handles all the use cases- creation of full databases, schemas and cloning (both full clone and Snap Clone) from a single management interface. The point tools out there handle only fraction of these use cases- some specialize in cloning while others specialize in seed database provisioning. Second, as stated in the previous answer, provisioning is only the initial phase of the lifecycle and a provisioning tool cannot be synonymous with a cloud management tool. Thanks Gordon for helping me make that point!

Sam and Cesar share the honors for the most difficult question that came right at the beginning. "Has it started?  Been on hold for a while ." was their reaction at two minutes past ten. This is possibly the most embarrassing one for me because I was caught in traffic. With due apologies for that, I wish my car operated like Enterprise Manager's  Database as a Service!

By Sudip Datta