We are migrating to Exchange 2007 and have a requirement to maintain a small public folder hierachy. This is mainly to support legacy Outlook clients but there are also a few shared items and forms etc. I plan to use a dedicated server as a public folder server but I'm not sure if I should opt for two for resillience. If I do, then those public folders will replicate using PF replication. Now, the documentation tells me that would exclude me from using CCR and other new replication technologies. However, can I assume that the statement only refers to the storage groups containing public folders? I assume that if I have two servers performing public folder services, that my other mailbox servers won't be limited in their replication options. I'm sure it just means that I can't use both CCR etc and PF replication on a public folder database but it would be nice to clarify my thinking.Also, if I did limit myself to one public folder server, and that failed for a period of time, would that mean that my legacy clients wouldn't be able to connect to Exchange? Obviously having only one server acting as a PF server isn't best practice, but I'd like to understand the impact of failure anyway.Thanks in advance all!

Yes it is not supported to have CCR & public folder replication but if you have only one PF server in your environment then you can put it on CCR since it doesnt have public folder replication. Reference: Cluster Continuous Replication and Public Folders http://exchangepedia.com/blog/2007/05/cluster-continuous-replication-and.html

But if I have two public folder servers and I use PF replication, I can still use CCR for my mailbox databases?

In that case... "If an unscheduled outage occurs, the public folder database will not come online until the original server is available and all logs for the storage group hosting the public folder database are available. If any data is lost as a result of the outage, CCR will not allow the public folder database to come online when public folder replication is enabled. In this event, the original node must be brought online to ensure no data loss, or the public folder database must be re-created on the clustered mailbox server in the CCR environment and its content must be recovered using public folder replication from public folder databases that are outside the CCR environment." - http://technet.microsoft.com/en-us/library/bb123996.aspx

Bear with me please Amit, your help is much appreciated. But what is the scope of "CCR Environment"? My plan at present is to have two seperate PF servers (no mailbox databases), a 6 mailbox servers (with no PF databases). If PF replication is enabled between the two PF servers does that preclude me from using any CCR technologies on the mailbox servers? In this scenario, are my PF servers considered outside the CCR environment?TIA.

Yes, if you are using separateservers just for PFs then you can use other servers to implement CCR for Mailbox database redundancy. Basically document says, you can not use both kinds of replications (PF and CCR) at a time to achievepublic folder redundancyand use either of them. BTW, just want to clarify that you can have maximum 2 nodes in CCR environment (one active and one passive) since you are planning it for your mailbox database servers.

Yes, Amit is right. You wouldnt have problem since the public folder server didnt mix into CCR environment. As said at the article provided by Amit: If more than one Mailbox server in the Exchange organization has a public folder database, public folder replication is enabled and public folder databases should not be hosted in CCR environments Public folder replication will enable automatically between those mailbox servers which has the public folder database, and not set as an active node or passive node in the CCR environment

Chaps, thank you both for your input. My question has been answered. Many thanks.