Cannot connect to certain computers via IP address using WMI

Overview

Cannot connect to certain computers via IP address using WMI.

Environment

All SAM versions

Cause

This issue is caused by an improper configuration or bad record on the DNS server. Microsoft uses DNS reverse lookups when trying to connect through WMI using IP addresses.

Resolution

Add a period, (.) to the end of the IP address when making any query. This forces WMI to go through DNS resolution.

Example: winmgmts:{impersonationLevel=impersonate}!\\192.168.1.123.\root\cimv2

In the SolarWinds.APM.Probes.dll.config file:

[WmiSettings Retries="3"
WaitToRetry="0:00:10"
ConnectOptions="BothAutoCorrectedFirst"
DoReverseLookupWhenFailed="true"/]

Retries - number of retries when trying to connect using WMI.
Replaces old [add key="WMI.Monitor.Retries" value="3"/]

WaitToRetry - interval between retry attemps.
Replaces old <add key="WMI.Monitor.WaitToRetry" value="10"> </add>

ConnectOptions

Default - use IP address
OnlyAutoCorrected - use only IP address + "." (if IP address is IPv4 address)
BothAutoCorrectedFirst - try to use AutoCorrected version first and then Default version
BothDefaultFirst - try to use Default version first and then AutoCorrected version

DoReverseLookupWhenFailed

If "true," then the Reverse DNS Lookup is executed and the log file contains IP address list of target machine to check if we are connecting to correct machine. You can find following message in the log file:
2012-02-23 12:36:43,766 [STP Pool:4 Thread #0] [C0] DEBUG SolarWinds.APM.Probes.WMI.WMIHelper - List of all IP addresses for '10.140.126.27': 2001:10:140:126:d083:e915:7c6d:48db;10.140.126.27