Exchange data changing rapidly 1

[slicksheos]

Hi, I have an Exchange 2007 Enterprise server. It hosts all 3 roles and is almost fully patched. It is for a 7 person company and the mail database is about 20GB. It is running on a VMware ESX 3.4 U4 environment and is sitting on a LeftHand iSCSI SAN. We vault our data online nightly using incremental backups. Every night the vaulting software determines that the data has changed to much to do an incremental backup, so it backs up the entire store. Additionally, we are doing SAN to SAN replication and that is seeing about 1GB of changed data every hour. I know that there is no way we have this much mail, and the logs are only about 15MB an hour. Am I missing something? The event logs are clean, the best practices analyzer is happy.. any suggestions? Thanks!

 

[Zelandakh]

SAN to SAN replication will do the deltas of the server since I assume your ESX is leaving the vmdk on the SAN. So 15MB of logs / emails per hour is probably right and 1GB is the whole server image. You'll be snapping the pagefile I'd guess.

 

[xmsre]

Please explain the vaulting software. As more than a few people know, I run on NetApp. I'm more than familiar with change deltas, so this is intersesting.

In Exchange 2007 SP1 or later, there are really tow things beyond user data that impact change delta; online maintenance and indexing. For a system in which no tuning of the online maintenance has taken place, start here:

A = Average message size
U = number of users
S = Average messages sent per day per user
R = Average messages received per day per user.

(S+R) * U * A = Base Change Delta (BSA)

log change delta - BSA * 2
Database change delta = log change delta * 1.4

If you gfollow the MS guidance, and reduce the window for OLM by monitoring the OLM pages read/Freed ratio, then:

log change delta = BSA * 1.2

Do the math.

XMSRE