Installation manual

Drive size
EMC has currently certified different FC and ATA/SATA-II drive capacities. EMC does not require
any specific disk size within the supported list of disk sizes and types. Select disk sizes and types
based on capacity and performance requirements.
Drive technology
The chosen technology must match the performance requirements of the customer application.
For OLTP environments, data warehouses, and environments where response time
1
is critical,
use FC drives. For backup-to-disk, longer term storage, and applications where response time is
not critical, use ATA/SATA-II drives.
Vault and configuration drives
The first five drives in a system are used as database and vault drives. These disks are used for
online upgrade operations, replication software management, and Navisphere configuration
management and tracking. The RAID group containing the first five drives of the system should
not be used for file types other than file-sharing LUNs and should be considered to already have
a busy LUN.
Navisphere uses the first three drives for caching online upgrade data. Heavy host I/O during an
online upgrade can cause the upgrade to time out, so it is recommended that before an online
upgrade commences, the host load be reduced to 100 IOPS per drive. Backups should not be
scheduled nor should backups be placed on hold during an online upgrade operation.
Simple and efficient storage system configurations
The minimum CX3-80 configuration consists of one SPS assembly, one SPE with two SPs, and
one DAE with five drives.
For DAEs with hot spares, configure 1x 8+1 and 1x 4+1 and one hot spare. For DAEs without hot
spares, create 3x 4+1 RAID groups.
1
Response time is defined as the difference in time from when the user begins the computer request until
the user gets the data requested or a write completion notification. Response time is how a human
measures performance.
Dell/EMC CX Series Initial Configuration
Best Practices Planning 14