student guide.pdf

Copyright © 2005 EMC Corporation. Do not Copy - All Rights Reserved.
Configuration Considerations
• Understand the applications on the host connected to the Symmetrix
system
– Capacity requirements
– I/O rates
– Read/Write ratios
– Read/Write - Sequential or Random
• Understand special host considerations
– Maximum drive and file system sizes supported
– Consider Logical Volume Manager (LVM) on the host and the use of data striping
– Device sharing requirements - Clustering
• Determine Volume size and appropriate level of protection
– Symmetrix provides flexibility for different sizes and protection within a system
– Standard sizes make it easier to manage
• Determine connectivity requirements
– Number of channels available from each host
• Distribute workloads from the busiest to the least busy
© 2005 EMC Corporation. All rights reserved. Symmetrix Foundations - 46
The best possible performance will only be achieved if all the resources within the system are
being equally utilized. This is much easier said than done, but through careful planning, you will
have a better chance for success. Planning starts with understanding the host and application
requirements.
Within the Symmetrix bin file, the emulation type, size in cylinders, count, number of mirrors, and
special flags (like BCV, DRV, Dynamic Spare) are defined. Each Symmetrix logical volume is
assigned a hexadecimal identifier. The bin file also tells the Channel director which volumes are
presented on which port, and the address used to access it.
From the Host’s perspective, when a device discovery process occurs, the information provided
back to the Operating System appears to be referencing a series of disk drives. The host is unaware
of the bin file, RAID protection, remote mirroring, BCV mirrors, dynamic sparing, etc. In other
words, the host “thinks it’s getting” an entire physical drive.
Symmetrix Foundations - 46