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Home > Success Center > Network Topology Mapper (NTM) > Missing connections on discovered nodes

Missing connections on discovered nodes

Table of contents

Updated February 22, 2017

Overview

This article provides brief information and reasons on NTM's inability to generate connections among discovered nodes.

Environment

All NTM versions

Detail

Invalid credentials
Use the Test at the bottom of the Add Credential Resource to verify before adding or modifying a credential.

 

Device does not support SNMP
NTM uses SNMP polling to retrieve CDP and LLDP data. Without these Layer 2 and Layer 3 data, NTM cannot map direct connections among discovered nodes.

In such a case, assuming a device does not support SNMP but supports and can respond to ICMP, NTM would the node as indirectly connected only to other relevant ICMP devices, through a Network Segment node.

For detailed information about Network Segments, see the Opening Maps sections from earlier versions of NTM documentation.

 

Device is configured not to return CDP/LLDP data by SNPM requests
The result is the same as in the case that the device does not support SNMP.

 

Timeouts are triggered due to slow response from a devices
If NTM is configured not to retry, or the specified number of retries fail, then the device is treated as an ICMP node.


You can modify timeout settings in:

SolarWinds.NTM.BusinessLayer.dll.config (\Program Files\SolarWinds\Network Topology Mapper).

<appSettings>
32 ³ Discovering Devices and Topologies
...
<add key="NtmICMPTimeout" value="5000"/>
<add key="NtmMaxSnmpReplies" value="5"/>
<add key="NtmSnmpTimeout" value="3000"/>
<add key="NtmSnmpRetries" value="0"/>
...
<add key="NtmWmiRetryInterval" value="1000"/>
<add key="NtmWmiRetries" value="3"/>
...
<add key="NTMVIMTimeout" value="3000"/>
...
</appSettings> 

 

Last modified
20:52, 26 Mar 2017

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