Hello,
There seems to be a lot of confusion about DAG and Symantec EV. I think the whitepaper "Technical Whitepaper - Enterprise Vault 9 Archiving from Exchange 2010.pdf" from Dan Strydom does solve some questions but not all. As a point the "Jounraldatabase1" on page 8 is hosted on MailboxServer1 has a copy on the DR MAilboxserver3 but there is not copy on Mailboxserver2.
Lets start with a sample that most middle site customer have and is also mentioned in the paper above on page 8.
2 x CAS
2 x Hardware Load Balancers
2 x MBX Server with DAG
MDB1 (Active on Server 1)
MDB2 (Active on Server 2)
Lets also asume they have a Backup Solution which handles the DAG and sees the DAG (Netvault and Netapp SME).
1) Microsoft says a Database which resides on a DAG Server should be DAG activated. (That would not be in sample with JOURNALDATABASE1). Either its DAG or non DAG but nothin between. But then you would have the IOPS + the Log traffic between the DAG additional.
2) Microsoft says that Journaling will give 15-20% more IOPS with Journaling
and to keep it in seperate DB
Some things we still don't understand or how we understand it before we asked here:
a) Best would be the Journaling DB to be in the regular DAG database. However you would have the 15-20% IOPS increase.?
b) Better would be per Server a seperate standalone DB for the Journaling. This will not failover. This will give EVENTS and error because the DB is NOT DAG activated and resides on a DAG Server. > Backup products may hang at a selection point for backup or restore because the can't handle the special DB (Let's just asume)
c) If we make a seperate standadlone Journaling Server to get rid of 1) IOPS 2) Problems with Events 3) Asumed problems with Backup components THEN we have the Problem that single Journaling Server is NOT Redundant.
How do you solve this in practice and whats the best way Symantec would recommend?
If you look at the Forums many customers seems to have problems with that. We just want to understand why and best practice.
Thank you for any help and your time. Any comment welcome.
Regards
Mike
http://www.symantec.com/docs/HOWTO57591
http://www.symantec.com/docs/TECH144726