We are planning to install our new exchange 2007 server in a cluster environment. i would like to know which clustering method would be best ?? CCR or SCC ??? Also i would to know if we go for Single Copy cluster then what are the advantages and disadvantages of using SCC for clustering purpose??? Looking forward to your feedbacks

Based on my research, CCR provide several advantages than SCC: Like less expensive to deploy; protect data by keeping a copy of each DB; less complicated to deploy, please view the link below for more http://technet.microsoft.com/en-us/library/aa997928(EXCHG.80).aspx SCC can't provide a copy for mailbox store; you have to use 3rd-party application to replicate data. CCR can provide a copy for store and auto-failover; it doesn't need shared storage or cluster hardware. If you have already got 3rd-party application for replica and want a cluster with fewer servers, then SCC would be the option for that, see the following for detailed info about SCC Single Copy Clusters http://technet.microsoft.com/en-us/library/bb125217(EXCHG.80).aspx

If i want to make my active server an additional domain controller with exchange 2007, do ialso need to install active directory onthe passive server ?????

DO NOT recommend to install exchange 2007 on DC. If you want to do this, yes, you need to make passive server a DC as well since it must be identical configuration between two nodes Please go through the tech article below for SCC deployment: Installing a Two Node Exchange Server 2007 SCC in a Virtual Server Test Environment http://www.msexchange.org/tutorials/Installing-Two-Node-Exchange-Server-2007-Single-Copy-Cluster-Virtual-Server-Environment-Part1.html