RE: clustered exchange environment

  • From: "Mulnick, Al" <Al.Mulnick@xxxxxxxxxx>
  • To: "'[ExchangeList]'" <exchangelist@xxxxxxxxxxxxx>
  • Date: Tue, 26 Oct 2004 17:23:23 -0400

Mike, Microsoft clustering uses a shared approach and requires a shared
resource with the exception of Majority Node Set clustering.  

Usually to do geographically disperse implementations, a third party is
used.  Many of those still are going to have distance limitations.  For
example, SAN based replication such as EMC's geo-span has a 5 k limit on
distance in synchronous mode.  To get asynchronous replication, you can go
further but you have a lag time then.  It's light physics mostly.

Whenver I see folks start to go down that path, I have to admit that I try
to dissuade them until they fully understand what they're requirements are.
For example, since clustering is a high-availability solution in the
Microsoft world, what does it guard against?  It guards against hardware
failure and the amount of time it takes to bring the service back on-line.
Some cannot tolerate more than 15 minutes of outage and it makes sense for
them to work with geographical clustering solutions as well as
fault-tolerant systems.  It costs a lot of money to do that and is complex
to say the least.  Others often find that they need to have a few people
back up and running immediately while others can function in their job
without email for a few days.  Some longer.  Some also realize that
historical data is not needed as quickly as the functionality of the
service.  They can explore other options at that point.  It's a rare company
that must have both historical data and functionality of service back within
minutes. They usually remember to give workstations to their people and
figure out a way to get their people where they can access the data too <G>

There's some great discussion about this sort of stuff in the disaster
recovery whitepaper on Microsoft's site if you're interested in following


-----Original Message-----
From: A. M. Salim [mailto:msalim@xxxxxxxxxxxx] 
Sent: Tuesday, October 26, 2004 4:27 PM
To: [ExchangeList]
Subject: [exchangelist] RE: clustered exchange environment


> Not possible
> Is it feasible to implement a clustered Exchange 2003 server 
> environment with two Windows 2003 Enterprise servers, each server 
> having internal IDE
> (ATA) drives not SCSI, and no "shared storage array" device?  i.e., 
> the two servers would keep in sync over a private ethernet link, 
> including Exchange 2003 Enterprise.

So clustering is only possible without a shared SCSI device?  So how do you
cluster two Exchange servers across the internet, say in different data
centers many miles apart?

best regards

List Archives:
Exchange Newsletters:
Exchange FAQ:
Other Internet Software Marketing Sites:
World of Windows Networking: Leading
Network Software Directory:
No.1 ISA Server Resource Site: Windows Security
Resource Site: Network Security Library: Windows 2000/NT Fax Solutions:
You are currently subscribed to this Discussion List as:
al.mulnick@xxxxxxxxxx To unsubscribe visit
Report abuse to listadmin@xxxxxxxxxxxxxx

Other related posts: