Planning an NDS implementation

Providing fault tolerance

If your network covers a large geographical distance, you might consider placing partition replicas on a server in another area. This accomplishes two things:

it allows users in that area to access your partition more rapidly
it provides a backup of your partition if a disaster destroys some local servers and replicas

You should have enough replicas of every Directory partition to provide sufficient database backup. If you lose a partition and do not have a replica of that partition, you could permanently lose access to a part of your Directory tree.

Note that directory replication does not provide fault tolerance for the file system. Only Directory information about objects is replicated. To provide fault tolerance for your files, you must take advantage of the host system's fault tolerance features.