Introduction
Note: for more comprehensive coverage of Exchange 2007 storage please see this blog post:
http://msexchangeteam.com/archive/2007/01/15/432199.aspx
This is the second of a four...
Updated Jul 01, 2019
Version 2.0
Blog Post
Andre,
I am not the specialist for Dell Storage but
if your MD1000 got two EMM in Split configuration and the internal BUS is separted you could go for CCR. You loose half of your storage in this config and you need two additional servers for the HUB/CAS role at least for redundency. Keep in mind that E2k7 does not allow any additional role to be installed on clustered mailbox servers. And you need a Windows server for the fileshare witness for CCR (can be one of the HUB servers).
So if you should go for CCR depends if any failure on one EMM will not affect the complete MD1000 (-> ask DELL). E.g. if a BUS failure on one side affects the complete MA1000 you only waste storage and CCR will not make sense here.
Another limit with CCR is that you can only have one MBX store / Storagegroup. If you assign mailbox limits on a per MBX store basis this could affect you as well.
Your second question is hard to answer without any additional details. But i provide one hint: The DB Write/Read Ratio is (almost) 1:1 now in E7 (latest recommendation i heared of was 75/25 - might change again for different solutions). This has an bad impact on the performance of any SATA Raid5 system. AT the other hand the I/O need if reduced - if you provide your servers with sufficent memory. I am still not able to provide detailed numbers. The load simulation tools for E7 are still not final. For this reason i cannot name any real-life values for different configurations. Maybe one of the Microsoft guys can add some values here.
Wolf
I am not the specialist for Dell Storage but
if your MD1000 got two EMM in Split configuration and the internal BUS is separted you could go for CCR. You loose half of your storage in this config and you need two additional servers for the HUB/CAS role at least for redundency. Keep in mind that E2k7 does not allow any additional role to be installed on clustered mailbox servers. And you need a Windows server for the fileshare witness for CCR (can be one of the HUB servers).
So if you should go for CCR depends if any failure on one EMM will not affect the complete MD1000 (-> ask DELL). E.g. if a BUS failure on one side affects the complete MA1000 you only waste storage and CCR will not make sense here.
Another limit with CCR is that you can only have one MBX store / Storagegroup. If you assign mailbox limits on a per MBX store basis this could affect you as well.
Your second question is hard to answer without any additional details. But i provide one hint: The DB Write/Read Ratio is (almost) 1:1 now in E7 (latest recommendation i heared of was 75/25 - might change again for different solutions). This has an bad impact on the performance of any SATA Raid5 system. AT the other hand the I/O need if reduced - if you provide your servers with sufficent memory. I am still not able to provide detailed numbers. The load simulation tools for E7 are still not final. For this reason i cannot name any real-life values for different configurations. Maybe one of the Microsoft guys can add some values here.
Wolf