Smarts IP 9.0: Interface instrumentation stays in Smarts IP topology even after interface is deleted in the device; Count of instrumentation objects is much higher than total managed P&I

Products

• VMware

Issue/Introduction

Symptoms:




Interface instrumentation stays in Smarts IP 9.0 topology even after interface is deleted in the device
When creating an interface, instrumentation is created upon the next Smarts IP discovery, but when deleting an interface, the instrumentation stays until it is manually deleted from the Smarts IP topology

Smarts IP 9.0 count of instrumentation objects is much higher than the total managed P&I

Environment

VMware Smart Assurance - SMARTS

Cause

There is a known issue with Smarts IP 9.0 code that will cause this issue in conditions like the following:

1. Create a loopback/tunnel/vlan interface on a device.
2. Discover the device in Smarts IP domain and you will find the interface object and its instrumentation in the repository.
3. Delete the loopback/tunnel/vlan interface.
4. Rediscover the device in Smarts IP.
5. The interface object is no longer in the repository, but the instrumentation is still there and the SNMP OIDs are still being polled.
   
   dmctl> findInstances .*::.*pi25cp01-ntsr003.*
   Interface_Fault_MIB2::I-Interface_Fault_MIB2-IF-pi25cp01-ntsr003.us.emc.com/71
   NetworkAdapter_PerformanceData_ifMIB::I-NetworkAdapter_PerformanceData_ifMIB-IF-pi25cp01-ntsr003.us.emc.com/71
   Interface_Performance_CiscoRouter::I-Interface_Performance_CiscoRouter-IF-pi25cp01-ntsr003.us.emc.com/71

The count of instrumentation objects will be much higher than the total managed P&I, due to this issue.

Resolution

Smarts IP 9.1 and later versions contain the fix for this issue. If you encounter this issue, you can do any of the following:

• Upgrade your environment to Smarts IP 9.1 or later
• Restart the Smarts IP domain to clear out all stale instrumentation objects
• Apply the workaround described in the following section

Workaround
To work around this issue without upgrading your Smarts IP environment, do the following:

CAUTION! The following workaround is an ASL code change that can have adverse performance implications for large Smarts IP topologies.

1. Open the custom-end-post.asl ASL script found here:
   
   <Basedir>/IP/smarts/rules/discovery/custom/custom-end-post.asl
   
    
2. Add the following ASL code in the START/do block:
   
   foreach instr (getInstances("ICIM_Instrumentation")) {
   instr = object(instr);
   if (instr->Instruments->isNull()) {
   print(instr ." is orphaned. Deleting");
   instr->delete();
   }
   }