The following alarm started to happen suddenly.

============================================================================
　The max interface speed (ifSpeed) of '<Interface Name>' on '<Device Name>' could not be determined! 
　Traffic alarms in percent of max speed cannot be issued. 
　Please override interface speed or set alarm options on actual values. 
============================================================================
 

Undetermined.

interface_traffic probe 5.45

Issue resolved after performing "Rediscover Interfaces"

Interface_traffic  - This probe is no longer supported as of October 1, 2017. This probe is replaced by the snmpcollector probe.

https://techdocs.broadcom.com/content/broadcom/techdocs/us/en/ca-enterprise-software/it-operations-management/ca-unified-infrastructure-management-probes/GA/alphabetical-probe-articles/interface-traffic-interface-traffic-monitoring-no-longer-supported.html

Snmpcollector documentation:
https://techdocs.broadcom.com/content/broadcom/techdocs/us/en/ca-enterprise-software/it-operations-management/ca-unified-infrastructure-management-probes/GA/alphabetical-probe-articles/snmpcollector-snmp-data-monitoring.html