For the purposes of failover, a file system can be called a replica when each file is the same size and has the same file size or file type as the original file system. Permissions, creation dates, and other file attributes are not considered. If the file size or file types are different, the remap fails and the process hangs until the old server becomes available. In NFS version 4, the behavior is different. See Client-Side Failover in NFS Version 4.
You can maintain a replicated file system by using rdist, cpio, or another file transfer mechanism. Because updating the replicated file systems causes inconsistency, for best results consider these precautions:
Renaming the old version of the file before installing a new version of the file
Running the updates at night when client usage is low
Keeping the updates small
Minimizing the number of copies