Call for Oracle support & training (800) 766-1884
Free Oracle Tips

Corporate Oracle Training
Custom Oracle Training
Oracle New Features Training
Advanced Oracle DBA Classes
Oracle Tuning Courses
Oracle Tips & Tricks
Oracle Training Links
Oracle Training Links
Oracle Training Links

We are top for USA Oracle Training Clients


Free Oracle Tips


Free Oracle App Server Tips


Oracle support

Oracle training

Oracle tuning


Remote Oracle

Custom Oracle Training


  Oracle Tips by Burleson

Oracle10g Grid Computing with RAC
Chapter 12 - RAC Design Considerations

Failure of the Fabric Switch

The fabric switch allows multiple hosts to access the SAN array. Failure of the fabric switch (or other interconnect equipment) can result in loss of performance or total loss of the application. If the SAN cannot be accessed then the database will crash and no one will be able to access it, even if all other equipment is functional.

SAN Failure

SAN failure can come in many forms. Catastrophic failure will, of course, result in total loss of the database. Failure of a single drive, if there is no hot spare or if the hot spare has been utilized, will result in severe performance degradation (by as much as 400-1000 percent) in a RAID5 situation where the data on the failed drive has to be rebuilt on the fly from parity information stored on the other drives in the RAID5 set. Even if there is an available "hot" spare, it still takes time to rebuild this hot spare from the parity data on the other drives. During this rebuild performance will suffer.  

Usually, SANs are configured with disk trays or "bricks" of a specific number of drives (usually 8 active and a single spare in each tray or brick). A single tray becomes an array, in the case of a RAID0+1 setup, the array will be striped across the 8 drives and would be mirrored to another tray in the array. Failure of a RAID0+1 drive has little effect on performance, as its mirror drive takes over  while the hot spare is rebuilt on an "on available" basis. In a RAID5 array, the 8 drives are usually set up in a 7+1 configuration (7 drives in a stripe set and one parity drive).

For more information, see the book Oracle 11g Grid and Real Application Clusters 30% off if you buy it directly from Rampant TechPress . 

Written by top Oracle experts, this RAC book has a complete online code depot with ready to use RAC scripts.

Remote DBA Services

Burleson Consulting can offer world-class remote Oracle database support at super-affordable prices.

Our remote Oracle DBA service provides 100% of the remote Oracle database administration needs for your company, and includes 24x7 access to our staff of 100% OCP Certified Oracle DBAs. 

We require a 12 month service commitment and include the following services:

  • Initial configuration review and problem identification
  • Installation of Oracle statistics collection mechanisms and quarterly database growth summaries
  • Hourly monitoring of your Oracle database for pending problems
  • Periodic performance analysis & identification of tuning activities
  • Twenty Four hour Oracle emergency support
  • Reporting and resolving all serious Oracle alert log messages
  • Free use of the BC TablePack, ServerPack and AuditPack services
  • Quick response emergency support for production database outages
  • Four hours of free remote DBA support every month. You can use these free hours for any DBA activity, including database analysis, system design, production migrations or personal mentoring.

For more information, please visit


Oracle performance tuning book



Oracle performance tuning software

Oracle performance tuning software
Oracle performance Tuning 10g reference poster
Oracle training in Linux commands
Oracle training Excel


email BC:

Copyright © 1996 -  2014 by Burleson Inc. All rights reserved.

Oracle® is the registered trademark of Oracle Corporation.