IBM System Storage TS7650G 3958 DD4, Installation Roadmap Manual

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3. The utility will automatically perform the tests in sequence. The client output
(server2 in the example below) will look similar to the following:
Note: In the sample output below the test ran for only 5 seconds instead of
300.
*** Latency
PING 9.5.53.33 (9.5.53.33) 56(84) bytes of data.
--- 9.5.53.33 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4001ms
rtt min/avg/max/mdev = 0.257/0.406/0.484/0.079 ms
*** Throughput - Default TCP
[
3] 0.0- 5.0 sec 56.6 MBytes 94.8 Mbits/sec
*** Throughput - 1 TCP stream(s), 1MB send buffer
[
3] 0.0- 5.0 sec 57.0 MBytes 95.0 Mbits/sec
*** Throughput - 16 TCP stream(s), 1MB send buffer
[SUM]
0.0- 5.8 sec 65.0 MBytes 94.3 Mbits/sec
*** Throughput - 127 TCP stream(s), 1MB send buffer
[SUM]
0.0-11.3 sec 127 MBytes 94.1 Mbits/sec
Number of TCP segments sent: 230536
Number of TCP retransmissions detected: 21 (0%)
Done.
See the next section for information about interpreting the results of the tests.
Interpreting the results
The utility performs five foreground tests (Tests 1-5 below), and one background
test (Test 6 below). The example outputs below are from the client side. Each of the
first five tests below ran for 300 seconds (-t 300), while the last test monitored TCP
performance during that time.
Test 1: Latency
This test checks the nominal network link latency and packet loss. Example result:
*** Latency
PING 10.0.13.194 (10.0.13.194) 56(84) bytes of data.
--- 10.0.13.194 ping statistics ---
120 packets transmitted, 120 received, 0% packet loss, time 119060ms
rtt min/avg/max/mdev = 57.403/78.491/104.451/9.872 ms
Interpreting the results:
v The average round-trip-time (rtt) was 78.4ms and there was 0% packet loss.
v
The latency in WAN topologies may vary, but should never exceed 200ms.
Contact your network administrator if latency reports more than 200ms, as it
may significantly decrease replication throughput.
v
Higher latency values will cause a major deterioration in replication throughput.
v Packet loss should be 0%. Any other value indicates a major network problem.
Test 2: Throughput - default settings
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IBM System Storage TS7600 with ProtecTIER: Installation Roadmap Guide