Appendix E. Protectier Replication Network Performance Validation Utility For Vtl Systems - IBM TS7600 with ProtecTIER Software Upgrade Manual

Appendix E. ProtecTIER Replication Network Performance
Validation Utility for VTL Systems
The VTL pt_net_perf_util utility's objective is to test maximal replication
performance between two future ProtecTIER VTL repositories by emulating the
network usage patterns of ProtecTIER's Native Replication component. This utility
will not predict replication performance, but it may discover performance
bottlenecks.
Before you begin
The requirements of this utility are as follows:
v Red Hat Enterprise Linux 5.4
v Standard external utilities expected to be in the current path: ping, netstat,
The pt_net_perf_util utility and the iperf tool it uses are installed as part of the
ProtecTIER software installation. To test the replication performance, use the
following tool:
v iperf 2.0.4
This utility has two modes of operation, client and server. The server has to be
started before the client. Before running the utility, shut down all other programs
on both the client and server ProtecTIER systems. The client is the ProtecTIER
system that transmits the test data and the server is the ProtecTIER system that
receives the data (also known as the target server). Based on the data sent by the
client and received by the server, the script outputs key network parameter values
which indicate certain attributes of the network. The goal of these tests is to
benchmark the throughput of the network. The most important benchmark is the
direction that replication will actually take place, i.e. the target should be tested as
the server since the flow of data will be to that server from the client. However, it
is also important to also test the reverse direction to measure the bandwidth
performance during disaster recovery failback. Network bandwidth is not always
the same in both directions.
About this task
In the following procedure, the goal is to test network performance between two
machines on a WAN, server1 and server2. Each test will run for five minutes.
Since there are five tests, the process will take a total of 25 minutes.
Procedure
1. Start the server mode of the utility on server1 by entering the following
2. Start the client mode of the utility on server2 by entering the following
© Copyright IBM Corp. 2011
getopt, echo.
/usr/local/bin/iperf
commands on the command line:
cd /opt/dtc/app/sbin
./pt_net_perf_util -s
command on the command line:
./pt_net_perf_util -c server1 -t 300
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