Router Throughput SLE

What Does the Router Throughput SLE Measure?

The Router Throughput SLE measures the percentage of time when the network throughput was optimal. The Router Throughput SLE is a measure of the network's ability to transmit and to receive traffic without impedance.

Classifiers

A classifier is a parameter that indicates whether a router is performing optimally or not. When the network's throughput success threshold is not met, Juniper Mist Routing Assurance collects and classifies the factors contributing to failures, into classifiers (also referred to as health indicators). The router throughput SLE monitors the following classifiers:

• Interface Anomalies─Monitors minutes when the throughput is affected by errors at the router's interface. The Interface Anomalies classifier has three sub-classifiers that help you identify issues:

  • MTU Mismatch─Displays minutes affected by Maximum Transmission Unit (MTU) errors and input errors on the router interfaces. MTU errors in interfaces occur when a packet size exceeds the maximum allowed size for a specific interface. MTU mismatch errors occur due to oversized data packets or incorrectly configured interface settings.

    You must ensure that the MTU value is consistent along the packet's path to avoid MTU mismatch errors. MTU mismatch will result in discarded or fragmented packets. In Juniper Networks routers, you can check for MTU mismatches in the MTU Errors and Input Errors sections in the output of the following CLI command:

  • Cable Issues─Displays minutes affected by faulty cables in the network.

  • Negotiation Failed─Displays minutes affected by failure of auto-negotiation. Auto-negotiation allows two devices to automatically agree upon communication parameters like speed and duplex communication. If auto-negotiation is not complete, it could mean:

    • One or both routers may have auto-negotiation disabled in their configuration settings.

    • The Ethernet cable between the routers might be defective, preventing proper auto-negotiation.

    • There might be a misconfiguration on either router that is causing problems with auto-negotiation (for example, incorrect speed or duplex settings).

    Failure of auto-negotiation and duplex conflicts can lead to latency on ports. Older models of routers might fail to achieve maximum speed and could operate at a lower link speed. This sub-classifier displays failure minutes that are caused by these issues.

In Figure 1, the Router Throughput SLE met the service level goal for more than 99 percent of the time. Interface Anomalies contributed to degraded router throughput 100 percent of the time.

Figure 1: Router Throughput SLE

Analyze Router Throughput SLE Score

The Root Cause Analysis section provides visualizations for distribution, timeline, and statistics for service level failures and enables administrators to understand the impact of these issues.

Click the View Insights button to navigate to the Router Insights page which gives you fine-grained details of the router events. You can use the Router Insights page to correlate router events that could have impacted the SLE.

Click the Router Throughput widget to navigate to the root cause analysis page. Click a Classifier to view its Sub-Classifiers.

• Statistics─The Statistics tab displays the success rate of the SLE metric and the average throughput of a router. Administrators can also view the distribution graph to understand the trend of throughput. You can view the Statistics tab only when you click the Router Throughput widget.

  Figure 2: Root Cause Analysis of Router Throughput SLE Score

• Timeline─The Timeline graph represents the trend of SLE failure minutes over a period. You can view the timeline graph for an SLE, a classifier and for a sub-classifier.

  You can move the slider across the graph. As you hover over the graph, a pop-up on the slider displays the failure minutes of every classifier and sub-classifier during the period. Colored vertical bars on the graph indicate various sub-classifiers.

  You can view the legend on the graph to interpret the plotted lines. Drag an area of interest to zoom in to the graph.

  Figure 3: Timeline

• Distribution─Use the Distribution tab to analyze service level failures by various attributes such as overall impact, failure rate and anomaly. The distribution tab displays these attributes for all the routers and their interfaces.

  You can sort the columns in the table by the column header. Click any column header to sort its entries. By default, the attributes are sorted by most anomalous.

  Table 1 describes the fields on the Distribution tab.

  Table 1: Fields on the Distribution Tab

  Fields	Description
  Name	Name of the Router.
  Overall Impact	Router's contribution (in percentage) to the SLE score.
  Failure Rate	Router failure rate (in percentage).
  Anomaly	Factor by which a router failed to meet the service level goal.

  Figure 4: Distribution

• Affected Items─The Affected items tab lists all routers that failed to meet the service level goal. From this tab, you can view affected routers' details such as MAC address, model number, failure rate and so on. The affected item tab also displays the count of routers that failed to meet the service level goal.

  You can sort the columns in the table by the column header. Click any column header to sort its entries. Table 2 describes the fields on the Affected Items tab.

  Click a router to view the Root Cause Analysis section for a specific router. The Root Cause Analysis section now displays the SLE metrics for the router. Click the View Insights tab to navigate to the Router Insights page. Use the Router Charts, the Router Interface Queues, and the BGP summary information of the router to debug the issues further.

  Table 2: Fields on Affected Items Tab

  Fields	Description
  Name	Name of the Router.
  MAC	MAC address of the router.
  Overall Impact	Router's contribution (in percentage) to the SLE failure.
  Failure Rate	Router failure rate (in percentage).
  Model	Router model name.
  Version	Version of Junos OS or Junos OS Evolved running on the router.

  Figure 5: Affected Items