If i have asset A on IP 123 scanned in 2016, and now i have asset B on the same IP 123 scanned on 2017, will the purge impact asset B since it is on the same IP? both assets are DNS tracked.
Scans are always by IP address (or agent) but reporting can be by DNS, like you have. This means that you report on the latest host to "own" that DNS name. The previous host that "owned" it shouldn't show in the report.
Purging a host will not recover a licence so I assume you don't want to recover it. In that case you can ignore the older data in your subscription.
Interesting. The report shows two different DNSs for the same IP. I have opened a ticket with Qualys just in case.
If you are purging by selecting the asset to be purged in VM-> Asset Search then it will only purge the asset you select. Think of the tracking token (IP, DNS, NetBIOS) as the primary key in the asset db for that network, deleting the row where the PK=namex won't impact the row where PK=namey even if some other column is the same value for both rows.
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