Release Notes

9 Migrating an Oracle Database to Dell EMC SC Series Storage | CML1001
3 Storage migration planning and considerations
A database migration involves moving a database from one system to a different system. Migration planning
is one of the most critical parts of the migration process. In additional to laying out the procedural tasks
relating to the migration, this process also needs to thoroughly identify and review the functional and
operational differences of the new platform since they have a direct effect on how the database environment
is managed and operated. Sufficient end-to-end testing also needs to be performed before the migration. This
paper does not discuss the process of the planning and migration, but it discusses certain tasks that
administrators should focus on.
3.1 Understand the environment
It is important to identify and understand the impact of migration to existing operating procedures. These
procedures might require updates because of the operational differences of the SC Series array. Such
operating procedures include, but are not limited to:
• Configuring, managing, and mapping volumes: Uses DSM and scripting tools
• Backup/recovery process: Includes snapshot technology
• Disaster recovery procedure: Introduces Live Volume and replication to enhance the disaster
recovery capability
• Replication process: Requires understanding the differences in replication modes and how to activate
the disaster recovery function in SC Series storage
• Monitoring of storage: Involves training the operation team on DSM
• Database cloning procedure: Uses thin snapshots and scripting tools
3.2 Define storage requirements
Both performance and capacity requirements are important criteria when choosing a successful storage
platform. It is recommended to start with performance first and then consider capacity, since performance
requirements usually require deeper understanding of the applications and the business.
3.2.1 Performance
In the majority of cases, performance statistics of the current environment are either absent or not fully
analyzed. This often leads to an unpleasant surprise after the database is migrated. Performance
expectations must be defined by quantifiable measurements and clearly communicated to all teams involved,
including the Dell EMC team so that they can properly size the SC Series array to meet the objectives.
Possible measurements included are covered in the following subsections.
3.2.1.1 IOPS, throughput, and latency
These are the most commonly used metrics when sizing and measuring storage performance. They are
application agnostic and focus only on the number and pattern of I/O packets. Some operating systems
provide native tools that collect basic IOPS information. For example, on Linux, sar and iostat come pre-
installed on the system. Other free utilities like atop and collectl are similar to sar but have additional
features. On Microsoft Windows
®
, Performance Monitor is readily available. Dell EMC also offers a free tool,
the Dell Performance Analysis Collection Kit (DPACK), to assist in collecting and analyzing system and
I/O performance data. For information on DPACK, check out the DPACK FAQ or contact the Dell EMC team.