NetWare Directory Services

7-20
Planning NetWare Directory Services Implementation
Developing a Replication Strategy
Developing a Replication Strategy
Replicas serve two purposes.
• They provide fault tolerance.
• They decrease WAN link traffic at login and authentication.
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.
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.
Decreasing WAN Link Traffic
If users are accessing the Directory tree through a WAN link, you can place
a read-only replica of the necessary partition on a local server so they don’t
need to cross the WAN link.
Storing a read-only or writable replica on servers that are across a WAN link
can be helpful because it cuts down on the traffic that has to cross the link
when users try to access that partition’s information. Nevertheless, there will
be some increase in traffic due to the synchronization of replicas.