Recently I had to do a recovery installation of Public Folder hosting DAG member, due to some hardware issues. The PF is hosted only on single server,  hence I had to plan for a quicker recovery to ensure the minimum downtime to Public Folder access. The process is simple if you are familiar with the recovery installation of Exchange Server 2010 DAG member.

1. Dismount the Public Folder (if the public folder is heavily used, select an off peak time to ensure lesser changes to PF)
2. Copy the Public Folder Database and Logs to the new server
3. Do a recovery installation of server to new hardware, follow Recovery Installation of a DAG Member with Multi Roles – Exchange Server 2010
4. Ensure that the Copied public folder is at the right location, and mount the database

You may follow the same procedure if you wish to do the recovery installation of Exchange Server 2010 server,

The process is as easy as mentioned, and can be opted for smaller organization without having much of issues. Only drawback is, the public folder will not be available during the recovery installation time. If you plan well, the downtime will be lesser than an hour.

-Praveen