We are currently the implication command to external IP addresses and it works great.
Is it possible to create a custom iplocation type lookup for sets of internal/corp IP ranges that we define too lookup cities and countries?
Yes, you have to create your own lookup containing the same information of the external addresses:
then you can add all the information you like, related to that location.
So you can call this lookup as a normal one using the IP address as a key.
Only one hint: put attention to the field names you use, it's easier to use the same of external addresses.
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