2 Replies Latest reply on May 9, 2018 12:15 PM by Andrew Waters

    How is the Best IP Score (best_ip_score) calculated?

    Paul Hecker
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      How is the Best IP Score (best_ip_score) calculated?



      I had a question from a customer concerning the primary IP address of a host.  They are running BMC Discovery 11.2 and asked how the primary IP address of a host is identified.  I had been working under the impression that the primary IP address was tied to the DNS lookup of the host name, thus the Best IP, but I wanted to provide a document reference.  And that was where I ran into difficulty.


      In looking at both the Discovery Access node - BMC Discovery 11.2 - BMC Documentation and DiscoveryAccess page - BMC Discovery 11.2 - BMC Documentation  documents, you see references for "Best IP Score (best_ip_score int)" and "OptNotBestIP" respectively, but I could not find a document reference that explained how the Best IP Score was calculated.


      I did find BMC Communities references that stated that the Best IP is basically the first IP address that can successfully access the device, Re: How does ADDM choose the Best IP of a Network device? All devices?, I also found a reference where the Best IP can be manipulated to an extent, Can you force/update the Best IP of a Host without destroying the node? , but that suggested that there was no Best IP calculation at all.


      Is anyone familiar with documentation that explains the Best IP Score (best_ip_score) calculation for a host or has an explanation on how it works?  Is the "Best IP", as noted, just the first successful IP used?


      Many thanks!




        • 1. Re: How is the Best IP Score (best_ip_score) calculated?
          Paul Hecker

          I continued digging and this one from 2015 appears to corroborate everything I've seen. 


          ADDM: In the Discovery Access, why are some IP's skipped with an End State of Opt1stScan or OptNotBestIP?



          The term "best IP" is somewhat misleading. If a device has, for example, 3 interfaces, ADDM will label whichever one it processes first as the "best" IP. When the scan then processes the other IPs and determines they are for the same device, they are labelled "not best IP". It's not possible to configure which IP ADDM will choose.


          So I may have found the documentation I needed but I would appreciate confirmation or any other documentation references.




          • 2. Re: How is the Best IP Score (best_ip_score) calculated?
            Andrew Waters

            best_ip_score is not very enlightening.


            The best IP has several factors involved:

            * which IP is scanned first,

            * which access methods are available on the IP, for example ssh is considered better than SNMP,

            * if the device is managed, for example a vCenter managing the device is better than scanning the device itself, and

            * IPs recognised as virtual are considered as worse than others (best_ip_score).

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