Migration options and considerations

Welcome friends to the Oracle University module on Migration Options and Considerations. I'm your host, Tshego. Let's get started. After completing this lesson, you should be able to learn about migration options and learn about migration considerations. A database deployment includes the following features and tools: Simple provisioning: The Create OCI DB System Instance Wizard is used to create a new database deployment. Patch application: Available patches are displayed through the OCI DB system console and can be applied with a single click. Patch application tool is provided and the DBA can decide when to patch. Automated backups: Automated backups can be set up. Cloud tooling provides for simplified backup and recovery operations with database backup service. Supported languages: OCI DB system supports several languages. Some of them are listed in the slide. Languages may have a dependency on Oracle database version. Advanced Security: Comprehensive security, including encryption of data at rest and data in transit is available. Local and remote Management: Enterprise Manager Database Control for Oracle Database 11G Databases and Enterprise Manager Database Express for Oracle Database 12C, 18C, and 19C, a part of the installation and can be used to monitor and manage the database. On-premise Enterprise Manager Cloud Control 13C can also be used to manage the databases. Please note that the Oracle OCI compute service with an Oracle DB image does not include any cloud tooling. Access to other ports. To access network protocols and services on a compute node by using a port other than port 22, you must do one of the following: Enable network access to the port. You can use the Oracle OCI DB system console to enable access to a port on a compute node. For more information, see enabling access to a compute node port at docs.oracle.com. Create an SSH tunnel to the port. Creating an SSH tunnel enables you to access a specific compute node port by using an SSH connection as the transport mechanism. To create the tunnel, you must have the SSH private key file that matches the public key that was specified during the database deployment creation process. For more information, see creating an SSH tunnel to a compute node port at docs.oracle.com. A storage volume is a persistent virtual disk. The volume can be attached to different database deployments, but only one at a time. The storage volume is used to store operating system files, Oracle database binaries, data files, control files, redo log files, and all files related to an Oracle database instance. That is, the password file, trace files, alert log, backup files, and so forth. You can manage a storage volume by using the Oracle OCI DB system console. Physical security of the compute node. The physical security of the server that hosts the database deployment compute node and database allocated to the customer is handled by Oracle. Customers have no access to the physical server. Operating system credentials to access the compute node. The following users are created when the database deployment is created: Oracle: A minimal privileged Linux user with normal shell access. This is the owner of the Oracle Software. OPC: A privileged Linux user with root command access and the only user with login permissions. Logging into the database deployment compute node requires secure access from remote hosts by using a secure Linux shell. When a database deployment is created, network access to the database deployments compute node is limited by default to SSH connections on port 22. This restricted access ensures that the instance is secure by default. To be able to log into the compute node, the OS user authenticates by using an SSH key pair. Operating system security. On the database deployment compute node, the user can perform the following operations: Load and run software in the compute node environment. You logs from the instance creation stored in subdirectories, A var/opt/oracle/log. User is responsible for OS security patches available through Yum as root. On the database -- deployment database instance, the Oracle OS user has full administrative privileges. Refer to the Getting Started with Oracle Guide for more details on subscribing to an Oracle Cloud Service trial and purchasing a subscription to the Oracle Cloud Service. The topics covered are: Requesting a Trial Subscription, Buying a Nonmetered Oracle Cloud Service, Buying a Metered Cloud Service, Activating Your Trial Subscription, Activating the Oracle Cloud Service. The following are some of the important factors to consider while selecting a migration strategy. Some will be covered in more detail in the following slides. Data size: Your strategy will differ in case of a multi-terabyte database. Application downtime: An easier migration strategy may not provide the benefits of minimal outage. Depending on application importance, you may want to migrate with minimal downtime. Network bandwidth. Data transfer from on-premises to cloud is entirely dependent on the customer's network bandwidth. FastConnect: The unpredictable nature of the Internet affects a migration to a cloud service. With FastConnect, you create high speed, dedicated, and low latency extensions, and thereby avail a true hybrid cloud setup. It also offers better security than exchanging a data over the Internet. Business criticality: For a tier one database, critical databases with least acceptable downtime, the strategy will first be to migrate the user acceptance testing and pre-production environments, followed by production. OS compatibility: Oracle database cloud provisions an Oracle Linux platform "Little Indian" for you. Your source database who is an Indianese, will also help in finalizing a migration strategy. Data Complexity: Some migration methods have limitations on the type of data. You must consider this before finalizing the migration strategy. A few of these are discussed later in this lesson. Conventional export or import refers to Data Pump conventional export or import. The terms fast, very fast, and very easy refers to a relative comparison between the migration methods. A lot of this depends on the size of the database. Some of these methods will be discussed in detail in subsequent lessons. The Apex version plays an important role in unplug or plug and remote cloning. An Apex CDB version mismatch between PDB versions is a fatal error. Some of these methods will be discussed in detail in subsequent lessons. An OCPU is defined as the CPU capacity equivalent of one physical core of an Intel Xeon processor with hyperthreading enabled or one physical core of an Oracle SPARC processor. For Intel Xeon processor, each OCPU corresponds to two hardware execution threads known as VCPUs. For Oracle SPARC processes, one OCPU corresponds to 8 hardware execution threads also known as VCPUs. When creating a database deployment on Oracle database cloud service, you choose the computing power for the associated compute node or compute nodes in the case of deployments that use Oracle real application clusters from a list of supported Oracle CPU and processor RAM combinations. A shape as a resource profile that specifies the number of OCPUs and the amount of memory to be allocated to an instance in Oracle Compute Cloud Service. If you're not sure what shape to choose, you should use your current on-premises hardware setup as reference. OCI is the only public cloud that supports bare metal and VMs using the same set of APIs, hardware, firmware, software stack, and networking infrastructure. You can see the two models on the slide. Bare metal instances are instances where customers get the full server. This is also referred to as a single-tenant model. The advantage here is that there is no performance overhead, no shared agents, and no noisy neighbors. On the other end of the spectrum are VMs when the underlying host is virtualized to provide smaller VMs. Also referred to as the multitenant model. The advantage here is flexibility in terms of choice of instance shapes. While creating compute instances, you can assign CPU and memory resources by selecting from a wide range of resource profiles called shapes, each of which is a carefully designed combination of processor and memory limits. Network bandwidth is based on expected bandwidth for traffic within a VCN. The dense IO instances are configured with 51.2 terabytes of local NVMe storage and are ideal for extreme transactional workloads that work on large datasets and require low latency and high throughput, such as big data and high performance compute applications. In case of standard VM instances, NVMe storage is not available. For all the shapes, block volume storage is offered. Some instance shapes in Oracle Cloud Infrastructure include locally attached NVMe devices. These devices provide extremely low latency, high-performance storage that is ideal for Big data, OLTP, and any other workload that can benefit from high-performance storage. Note that these devices are not protected in any way. There are individual devices locally installed on your instance. Oracle Cloud Infrastructure does not take images, backup or use RAID or any other methods to protect the data on the NVMe devices. It is your responsibility to protect and manage the durability of the data on these devices. Migration connectivity options are FastConnect, IPsec VPN, and Internet Gateway. Regardless of how you load data into your databases, it is recommended to use a bulk data transfer mechanism to move data close to your OCI DB system instance before performing a data loading operation. For smaller datasets, the data can easily be copied over to the Internet. However, when the data set is large, this may not be feasible. To accommodate these situations, you can use the Oracle Public Cloud data transfer services to physically send large data sets to the Oracle Public Cloud. For more information about using the Oracle Public Cloud data transfer services to move large data sets, refer to docs.oracle.com. Thanks for hanging with me on the module on migration options and considerations. I hope you've learned something useful.