Your company has a Active Directory forest. The forest contains two sites named Site1 and Site2. You
plan to deploy Exchange Server 2010 servers in both sites. You need to plan a high availability subnet
for the Mailbox servers that meets the following requirements:
• Users must be able to access their mailboxes if a single server fails
• Users must be able to access their mailboxes remotely if a single site becomes unavailable
What should you include in the plan?
A.
Deploy two Mailbox servers in each site. Install and configure continuous cluster replication (CCR).
B.
Deploy one Mailbox server in Site1 and one Mailbox server in Site2. Install and configure
continuous cluster replication (CCR).
C.
Deploy one Mailbox server in Site1 and one Mailbox server in Site2. Install and configure
continuous cluster replication (CCR).
D.
Deploy two mailbox servers in each site. Create two database availability groups (DAGs) named
DAG1 and DAG2. Add the Mailbox server from Site1 to DAG1 and the Mailbox servers from Site2 to
DAG2.
Explanation:
Pass4Sure had C as the correct answer and it looks like it is possible based on the following info
however I did find this blurb CCR cluster nodes could be located in separate datacenters in order to
provide site-level redundancy, but since CCR was not developed with site resiliency in mind, there
were too many complexities involved with a multi-site CCR cluster solution (for details on multi-site
CCR cluster deployment take a look at a previous article series of mine). This made the Exchange
Product group think about how they could provide a built-in feature geared towards offering site
resilience functionality with Exchange 2007.
http://www.msexchange.org/articles_tutorials/exchange-server-2010/high-availabilityrecovery/uncoveringexchange-2010-database-availability-groups-dags-part1.html
I really think that D is the better answer for this question
Exchange 2007 introduced LCR, CCR, SCC and SCR LCR (local continuous replication) this was mainly
used for small business who wanted to replicate a copy of their Exchange database to another disk
on the same server.
SCC (Single copy cluster) was what I would call a traditional Exchange cluster which used shared
storage to host the Exchange database.
Basic architecture of an SCC
CCR (cluster continuous replication) was used to replicate Exchange database information between 2
Exchange server allowing for hardware and storage redundancy but was limited to 1 Active node and
1 Passive node.
Basic deployment of CCR
SCR (standby continuous replication) was introduced in Exchange 2007 SP1 to provide the ability to
replicate Exchange databases to an disaster recovery location.
How did it use to work?
The concept of a DAG and how it functions I believe is easier learned by someone who hasn’t
worked with Exchange clusters previously. In Ex 200X an Exchange server was installed as either an
Active or Passive cluster node at the time setup.exe was run. Depending on which version of
Exchange you installed you had to create an Exchange virtual server (EVS) which was changed to
cluster mailbox server (CMS) in Exchange 2007. When a user connected Outlook the mailbox server
name was a clustered resource which moved between any number of nodes on the Exchange
cluster. This allowed for no end user configuration changes all the resource moved between physical
servers An Exchange database was associated with the clustered resource and when you open
EMC/ESM the only Exchange server name that was shown was the clustered node, let’s call is CMS1.
That means database one would always belong to CMS1 even when this moved between physical
machines.
Here comes the DAG
So now it’s time to forget everything that I just mentioned previously in this article about Exchange
clustering.
What has been removed?
No more EVS/CMS
Database is no longer associated to a Server but is an Org Level resource
There is no longer a requirement to choose Cluster or Non Cluster at installation, an Exchange 2010
server can move in and out of a DAG as needed
The limitation of only hosting the mailbox role on a clustered Exchange server
Storage Groups have been removed from Exchange
Is anything the same?
1. Window Enterprise Edition is still required since a DAG still uses pieces of Windows Failover
Clustering CCR cluster nodes could be located in separate datacenters in order to provide site-level
redundancy, but since CCR was not developed with site resiliency in mind, there were too many
complexities involved with a multi-site CCR cluster solution (for details on multi-site CCR cluster
deployment take a look at a previous article series of mine). This made the Exchange Product group
think about how they could provide a built-in feature geared towards offering site resilience
functionality with Exchange 2007.
