After customers upgrade their ASA to 8.4.5 customers might notice that their netflow collectors fail to interpret the events from ASA.
An example error for Solarwinds NTA is:
NetFlow exports from the Asa cannot be processed by Solarwinds NTA. The error is as follows: NetFlow Receiver Service [SECUOMNF01] received an invalid V9 template with ID from device
The reason for this is the changes made to the ASA netflow export capability in the 8.4.5 code. Information about the same is detailed in the following ASApedia article: NetflowEbay
Basically there was a new capability added to the flow export capability by the introduction of a new periodic flow-update event to provide periodic delta byte counters over the duration of a flow. Prior to the enhancement byte counters were reported only in the flow-creation and flow-teardown records, with an aggregate counter for both the forward and reverse flows. This enhancement is meant to replace the aggregate counter with separate forward and reverse flow byte counters to allow customers to examine the directionality of byte flow.
Please note this is not a problem on the ASA, but collector side code needs to be modified to understand the new changes that were made in the ASA flow export capability.
The enhancement is noted in the ASA release notes for 8.4.5 as well: