"Update Network Resource Location" task is using spUpdateAssetLocationUsingSubnetLocation stored procedure and SQL function fnAssetsSubnetLocation to gather list of resources based on their subnets and assign them to defined Locations.
SQL part is looking for records in two tables - Inv_AeX_AC_TCPIP (collected by Basic Inventory) and Inv_Device_TCPIP (typically result of Network Discovery tasks) and calculating subnets and locations to be changed.
It was identified that in some cases, Inv_Device_TCPIP table may have multiple records for the same resource (over the time it may change IP address, Subnet Mask, even MAC Address). This is causing issues with correct subnet/location identification, even if Inv_AeX_AC_TCPIP has latest data from managed clients (in case if Network
Resource is computer).
Fix with steps how to install is included in 7.6 post-HF7 cumulative update for Asset and CMDB solutions.
Prerequisite for installation is SMP 7.6 HF7. No additional post-HF7 cumulative fixes are required.
Fix is changing the calculation logic behind 'Update Network Resource Location' task. When executed, it will calculate necessary TCP/IP information (subnets, subnet masks, etc) using data from same SQL tables. But if data for the same resource will be in both tables, or only in Inv_AeX_AC_TCPIP, then it will be taken from the Inv_AeX_AC_TCPIP. If only in Inv_Device_TCPIP, but will have multiple rows, then will be taken from there based on latest '_id' field.
Note: Same changes will be merged also in upcoming 8.1 RU1. Should you need fix for version 8.0, please contact Symantec Support team.