当网络发生延迟问题时,可以在交换机上检查端口到端口的延迟。对于Cisco Nexus交换机,有一种称为延迟测试的方法,允许管理员规划网络拓扑,管理响应响应并标识出网络应用问题的原因。这种方案也能够提供对于延迟敏感型应用的SLA。
默认,交换机已经激活了端口对的瞬间模式延迟监控(Instantaneous mode latency monitoring)。这个模式可以测量每个数据包的交换机延迟。这个交换机延迟工具工作在线性速率上,也就是不需要数据包采样。
Copy switch# show hardware profile latency monitor interface ethernet 1/1 interface ethernet 1/6
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Egress Port: Ethernet1/1 Ingress Port: Ethernet1/6 Mode: Inst
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| | Minimum | Maximum | Average |
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| cnt | 890 | 1020| 960 |
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Copy if base ≤ latency < base + step, increment CNT0
if base + step ≤ latency < base + 2 * step, increment CNT1
if base + 2 * step ≤ latency < base + 3 * step, increment CNT2
if base + 3 * step ≤ latency < base + 4 * step, increment CNT3
Copy switch# show hardware profile latency monitor interface ethernet 1/1 interface ethernet 1/6
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Egress Port: Ethernet1/1 Ingress Port: Ethernet1/6 Mode: Linear Histogram
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| Range| 800-840| 840-880| 880-920| 920-960|
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| cnt | 123009| 556009| 640003| 450243|
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