After replacing Automation Server hardware the SNMP "msgAuthoritativeEngineID" changes, is this a possible security breach?
SNMP Management console
This is intended behaviour and part of the snmpV3 implementation as described in RFC3414
The msgAuthoritativeEngineID value contained in an authenticated message is used to defeat attacks in which messages from one SNMP engine to another SNMP engine are replayed to a different SNMP engine. It represents the snmpEngineID at the authoritative SNMP engine involved in the exchange of the message.
When an authoritative SNMP engine is first installed, it sets its local value of snmpEngineID according to an enterprise-specific algorithm (see the definition of the Textual Convention for SnmpEngineID in the SNMP Architecture document [RFC3411]).
The handling of this is not a StruxureWare Building Operation server activity. This is standard functionality as defined by the Automation Server's Linux platform and net-snmp protocol stack.