Chapter 22. Replication and DR deployment with backup applications 399
22.5.4 Tivoli Storage Manager reclamation and housekeeping
When using Tivoli Storage Manager and ProtecTIER CIFS replication, configure your Tivoli
Storage Manager reclamation to avoid the Tivoli Storage Manager reclamation process
colliding with the replication window of ProtecTIER. For maximum efficiency, choose
dedicated windows for ProtecTIER replication and backup server housekeeping afterward.
In the first case, bond all the FSI ports under a single virtual interface (this is also the default
setup). If the user wants to divide the ports among several different virtual interfaces, there
could be a performance issue that using a different subnet per IP address resolves. This is
not a ProtecTIER problem, and is the way the network behaves.
22.5.5 Replication in an FSI environment
You can use the ProtecTIER product to configure replication policies to replicate file system's
directories and all objects contained in these directories recursively to remote ProtecTIER
repositories without any disruption to the operation of the file system as a target for backup. It
is possible to define up to 64 source directories per replication policy, and to define up to
three remote ProtecTIER destinations. The replicated data in the remote destination can be
easily used to restore data in the case of a disaster recovery, or in the case of a disaster
recovery test (without any interruption to the backup and replication procedures).
It is important to allow the ProtecTIER product to supervise all changes made to a directory,
or to a set of directories, that are constantly defined within a replication policy. Therefore, you
should not disable a replication policy, unless this policy is no longer considered relevant. If
there is a scheduled maintenance of the network used for replication, it is possible (though
not mandatory) to
suspend the replication to a specific destination. Suspend allows the
ProtecTIER product to continue supervising all of the changes made; it does not attempt to
send the replication data through the network for the time defined by the suspend operation
(note that the suspend operation is limited in time).
In the case where a policy was disabled for some reason, a new Replication Destination
Directory (RDD) must be defined to re-enable the policy. The ProtecTIER product does not
need to replicate all of the data from scratch if the old RDD was not deleted. It needs to create
only the new structure and metadata within the new RDD. Therefore, you should not delete
the old RDD until a new cycle of replication to the new RDD is over
In the second case, it is alright to have two IP addresses in the ProtecTIER server on the
same subnet, because you have two different hosts, and the issue of using the same subnet
mentioned in the first case is not relevant.
22.6 Replication optimization
This section describes the concepts and procedures related to optimizing replication
performance, including the procedures to improve operations.
22.6.1 General replication performance considerations
A single node ProtecTIER system has two 1 GBps (GbE) dedicated replication Ethernet ports
and delivers a maximum throughput of:
190 MBps in physical data-transfer terms
1400 MBps replication of nominal data (amount of data before deduplication)