In today’s highly connected world, directory servers are the IT cornerstone of many businesses. These components of the corporate infrastructure are the foundation of authentication systems for internal and, more commonly, external user populations. Managing a directory server with several hundred internal users is not all that difficult. However, managing a directory server with several million external users in all 24 time zones throughout the world is a much more daunting task.

IBM® Security Directory Server software can handle millions of entries, given the right architecture, configuration, and performance tuning. However, that tuning can differ greatly from tuning for a smaller server with only a few hundred thousand entries. Managing and tuning a directory server of this size requires a change in mindset. Tuning and performance must be a focus even before the hardware is ordered. A proactive approach must be taken after installation also, including the pretuning steps to better interface with other products to make installations and migrations successful, and then regular maintenance to keep the directory running smoothly.

This IBM Redbooks® publication is the accumulation of lessons learned in many different real-world environments, including a 24-server fault tolerant configuration with more than 300 million entries. The authors pooled their knowledge and resources to provide the most comprehensive performance view possible, from hardware to software, sort heaps to buffer pools, and table cardinalities.

In large directory server deployments, use this document as a guide for how to get the right fit for your environment.

Chapter 1. Service level objectives and agreements

Chapter 2. Designing your directory for optimal performance

Chapter 3. Time to do a health check

Chapter 4. Tips for tuning DB2 performance

Chapter 5. DB2 settings related to LDAP

Chapter 6. Using LDAP_MAXCARD and IBMSLAPD_USE_SELECTIVITY

Chapter 7. Tools and scripts

Chapter 8. Why you must use runstats

Chapter 9. When and how to run reorg

Chapter 10. LDAP searches and slow operations

Chapter 11. Indexes and direct I/O operations

Chapter 12. Disk striping and RAID

Chapter 13. Distributed directory

Chapter 14. LDAP replication information

Chapter 15. Adding a new LDAP server to an existing enclave

Appendix A. Special operating system tuning for IBM Directory Server

Appendix B. How to apply fix packs to an LDAP server

Appendix C. IBM DB2 UDB concepts and definitions

Appendix D. DB2 UDB quick reference guide

Appendix E. Directory Server backup and restore methods

Appendix F. Checklists

Appendix G. Additional material