Device Crashes Test

In the context of a Cisco SD-WAN overlay network, port hopping is the process by which devices try different ports when attempting to establish connections with each other, in the event that a connection attempt on the first port fails.

If a controller device/component - Cisco vBond Orchestrator, Cisco vManage, or Cisco vSmart Controller - is down or has crashed for any reason and the vEdge routers remain up, when the controller device comes back up, the connection between that device and the vEdge router might shut down and restart. This behavior occurs because of port hopping. When one device loses its control connection to another device, it port hops to another port in an attempt to re-establish the connection. For example, when Cisco vBond Orchestrator crashes, Cisco vManage might lose or close all its control connections. Cisco vManage then port hops, to try to establish connections to the Cisco vSmart Controllers on a different port. This port hopping on Cisco vManage shuts down and then restarts all its control connections, including those to the vEdge routers.

If a component crashes frequently, the connections will also be frequently closed and re-established. This may affect the performance of the entire Cisco SD-WAN overlay network. To avoid such performance degradation, it is necessary to figure out how frequently each component of the Cisco SD-WAN appliance crashed. The Device Crashes test helps administrators in this regard!

This test reports the number of times each component of the target Cisco SD-WAN appliance crashed. The detailed diagnosis of this test will help administrators figure out the time during which the crash occurred and the name of the crash file. Using this test, administrators can analyze the reason behind such crashes and rectify issues before end users start complaining of frequent failures on the overlay network.

Target of the test : Cisco SD-WAN

Agent deploying the test : An external agent

Outputs of the test : One set of results for each component of the target Cisco SD-WAN that is being monitored.

Configurable parameters for the test

Parameter	Description
Test period	How often should the test be executed
Host	The IP address of the host for which this test is to be configured.
Port	Specify the port at which the specified Host listens to. By default, this is NULL.
Username	By default, the eG agent executes REST APIs on the target appliance to collect the required metrics. For the eG agent to execute the REST APIs, a special user with monitoring privilege is required. Specify the name of such a user in this text box.
Password	Specify the password corresponding to the user mentioned in the Username text box here.
Confirm Password	Confirm the Password by retyping it here.
REST API Port	By default, the REST API Port is set to none. This implies that by default, this test connects to the default port to execute the REST API commands and collect the required metrics. In some environments however, a different port can be used to execute the REST API commands. In such case, specify that port number against the REST API Port text box.
SSL	The eG agent collects performance metrics by executing REST APIs on the target appliance. Typically, the REST APIs can be invoked through HTTP or HTTPS mode. By default, the eG agent invokes REST APIs using the HTTPS mode. This is why, the SSL flag is set to Yes by default. If the target appliance is not SSL-enabled, then the REST APIs can be accessed through HTTP mode only. In this case, set the SSL flag to No.
Detailed Diagnosis	To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option. The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled: The eG manager license should allow the detailed diagnosis capability Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.

Measurements made by the test

Measurement	Description	Measurement Unit	Interpretation
Total crashes	Indicates the number of times this component crashed.	Number	The detailed diagnosis of this test reports the crash index, crash time and crash file.