Symptom

ASR 1K router running IOS-XE 16.6.x code may experience a crash in the "cpp-mcplo-ucode" process in an area of code related to NBAR / MTP.

Conditions

Issue was first reported when a router began handling a higher volume of erratically-patterned SIP "200 ok" and "options" traffic that is in turn handled by NBAR / MTP. However, SIP packets may not be a strict requirement to hit this bug.

Workaround

Disable NBAR temporarily. In at least one instance, removing the below config was found to stop the crashes: flow record XXX collect application name <=====

Further Problem Description