Do I need an Exchange Cluster ?

[Barakka]

I have an Exchange 2003 server on our main site (where the web connection is) - two sites total. Currently upgrading the LAN and WAN services to increase fault tolerance and speed. As part of this we are going for a second

http://WWW connection

at the second site.

I have been looking at the options for running Exchange in a Geographically Distributed Cluster configuration to provide fault tolerance/failover as one of the sites is prone to power failures (the main site). Does an exchange cluster operate in a master-slave setup, i.e. will one site have the main exchange server where mail is distributed from and repicate itself to the second site, or would both sites have a live server each replicating to the other.

Ideally i'd like to move away from one site distributing all the mail over the WAN, it's a pain when a user from one site sends an email and it has to go over the WAN to get to the mail server (especially if it's got a 10MB attachment). Is this something that Clustering can help with or can it only be done using two Exchange sites and lose the failover ability ?

TIA

 

[xmsre]

The downside of a geographically dispersed cluster is that you go from a shared disk model to a replicated disk model. You'll need enough bandwidth, and the mirroring software/hardware to keep the two sets of disk in sync.

It really sounds like you want redundancy in your message routing architecture. That has nothing to do with clustering. Try clearly defining your objectives and reposting on the exchange 2003 list.

 

[Barakka]

Thanks for the reply, will post on the Exchange list.

 

[Barakka]

I have posted into the Exchange list, but looking at the suggestions and then looking into this further I am still coming back to the Cluster option.

We have a two site configuration with

http://WWW lines

at each site, configuration means that email will come into both sites randomly for the same single email domain. Ideally we want an email server at each site, that will respond locally and deliver the message to its intended recipient. Should we lose a site we want the other site to take over seamlessly, hence the sway towards GeoClusters.

Few questions regarding GeoClusters... obviously hardware for the replication elements is crucial, and possibly some 3rd party software linked to this... any pointers ?

What sort of bandwidth is it likely to require for the cross site replication (we have around 150-180 mailboxes, about 5GB total).

Also, in the event of a site failure, obviously the remaining site will take over seamlessly, but what happens when the other site comes back on-line ? Does it re-synchronise ? everything ? or is there logging involved ?

Thanks in advance

 

[xmsre]

You can answer the bandwith question by looking at writes/sec fr the volumes you intend to replicate.

Maybe you should look at Veritas Cluster Server. It's sort of like an automated hot standby.