Specifications
DATA CENTER BEST PRACTICES
SAN Design and Best Practices 60 of 84
fig11_SAN_Design
Host Tier
Storage Tier Tape Tier
Figure 40. The same edge-core-edge tiered topology.
The key drivers for data recovery include the following:
•How quickly access to data is restored, called the Recovery Time Objective (RTO)
•The point in time in which the last valid data transaction was captured, called the Recovery Point
Objective (RPO)
•Where the recovered data is located
Improving the Backup Infrastructure
Determine if the existing backup infrastructure can support expanding SANs driven by data growth:
•Look at the backup schedule and how long it takes to complete the backup, to see if there are better time
periods to run the job, or schedule to a different library for faster completion.
•Use tape multiplexing or compression.
If budgets permit, other options to improve backups to meet business objectives include the following:
•Add additional drives or libraries.
•Deploy a deduplication appliance.
•Use Virtual Tape Libraries (VTLs).
From a SAN perspective, consider the following:
•Add additional ISLs, or break down existing trunks into no more than two ports in the trunk to create TI Zones.
This minimizes the impact of backup trafc on other application trafc.
•Make sure that there are redundant paths to the backup tier (see the section on Device Placement
for details).
•For Brocade DCX/DCX-4S Backbone chassis with open slots in the core, add a high-density port blade, such
as the Brocade FC8-64, to expand the backup tier and add additional backup devices.
To reduce the time to recover from a backup, implement a two-tier disk-tape system with incremental backup to
disk and migration to tape in off-hours and full backups only during downtime, such as on weekends. Another
option is to implement a Continuous Data Protection (CDP) system, in which after a full backup only changed
les or disk blocks are backed up. This provides the ability to restore at a granular level.
For a detailed discussion of backup and recovery concepts and issues, see Strategies for Data Protection, by
Tom Clark, on Brocade Bookshelf (www.brocade.com/bookshelf).