I have researched , studied & thru some tranings gathered below info that I want to share.
1. By default exchange 2010 enables scheduled as well as continuous maintenance on databases. We should disable one of the options after installation as it generates high IOPS & it is doing the same thing again. Recommended from is to disable the scheduled one.
2. If we are planning for more than 4000 users per server then roles should be split.
3. Exchange 2010 now uses 32k page size instead of 8K in exchange 2007 so it would be good if page size on storage can be changed to 32k, although in case of exchange it will help in performance improvements by 1 to 2% only.
4. Plan for large databases for exchange 2010 for improving performance, small databases reduces performance in 2010. Start from 2Tb.
5. At all times 40% of the space should be free.
6. 20 to 22 spindles in raid at the backend storage for NetAPP.
7. De-duplication will help more when databases are more than a TB(30 to 35%), below 1 Tb de-dup will not benefit that much.
8. Verification of backups to be off in DAG environment (recommended by NetAPP) As verification takes too much time in 2010 & also no other DAGs can be backed up during verification phase.
9. Re-seeding if required will take a lot of time (obviously because of large databases) 2010 can take week as well due to larger database, so Snap-manager for exchange can help the reseeding process & complete it in minutess.
10. In a DAG if there are multiple databases that needs to be reseeded only one can be reseeded at one time.
11. 1 :1 ratio i.e. 1 database in one LUN & 1 log in separate 1 LUN. If multiple databases are in a single LUN then restore will not be successful. If multiple database logs are in one LUN then up-to the minute restore will not be successful.
12. DE-duplication should be done before backup. (after backup it will have no benefit till the retention is reached)
Disclaimer:- Above is for refrence only, Please research yourself & take advice from porfessional services before designing Exchange in your Organization.