Devices may appear to me mapped to a different IP address during the discovery

Products

• VMware Smart Assurance

Issue/Introduction

This article covers the use-case where devices are associated with a different IP address when the Management IP address is classified as Virtual IP. 

Environment

Smarts 10.1.X

Cause

• The IP addresses reported show following properties: (where X.X.X.X is the management IP address and Y.Y.Y.Y is the IP address the device has been discovered with). Highlighted the PartOf() relationship for each IP address.

Properties obtained from the command: dmctl -s <AMPM Domain> get IP :: <Insert the IP Address instance here>

IP-X.X.X.X
HostedBy =
MonitoringEnabled = TRUE
IsManaged = FALSE
PartOf = { HSRPGroup::HSRP-GROUP-X.X.X.X }
Underlying = {  }

IP-Y.Y.Y.Y
HostedBy = DeviceClass::Device_Name
MonitoringEnabled = TRUE
IsManaged = TRUE
PartOf = {  }
Underlying = { SNMPAgent::SNMPAgent-Device_Name }

• As per the Smarts logic, All the IP addresses which are part of HSRP Endpoints are considered to be Virtual IP addresses.
  The classification is due to its behavior of being associated to more than one system.
  The only way to restrict the ping is to unmanage the underlying IP address in the HSRP Endpoint. By unmanaging the IP address, the instrumentation object is removed and the ICMP ping does not occur.
  
  
• Same is explained on the code under: ic-end-virtualip.asl script reference as below:
  

      /* Now the device can have an virtual IP address that is actually part of another device. */
      /* So we just check if this device does have an underlying relationship with HSRPGroup.   */
      /* If NO, then we just skip this step of disassociating the IP address from the device.   */
        .....
        .....
        .....
      /* If a device was discovered using a virtual IP then 
         change the AgentAddress of the SNMPAgent with a non-virtual IP */

         
• We can see that the IP Address: X.X.X.X  gets disassociated from the SNMPAgent and Device->HostedBy relationship in the discovery logs:
  [March 25, 2025 at 2:28:56 PM GMT +101ms] t@683992832 Discovery #2
ASL_MSG-*-ASLP-discovery/ic-end-virtualip.asl: disassociate IP: X.X.X.X from: SNMPAgent-Device_Name
  
  
• As IP-Y.Y.Y.Y is not a part of any HSRP or VRRP group, the Device <-> IP relationship is established:
  [March 25, 2025 at 2:28:52 PM GMT +219ms] t@683992832 Discovery #2
ASL_MSG-*-ASLP-discovery/ic-ip-address.asl: IP list 1: Associate IP: Y.Y.Y.Y with SNMPAgent-Device_Name

Resolution

Please check with the device administration team if the IP address: X.X.X.X should be classified under HSRP Group, and evaluate the existence of the IP address X.X.X.X on the HSRPMIB ciscoHsrpMIB (.1.3.6.1.4.1.9.9.106)

The Management IP Address should not be configured to belong to any HSRP or VRRP groups, and hence need to be configured correctly on the device end. 

Additional Information

Documentation Reference:

Performance and Monitoring Question 5: Why does IP Availability Manager ping all the HSRP Endpoints as a part of monitoring? Can we set the HSRPEnabled to True and stop the ICMP ping monitoring?