5 Replies Latest reply on Dec 8, 2008 1:58 PM by tdvojmoc

    Change of SNMP ifIndex

    tdvojmoc

      How Orion NPM distinguishes interfaces and how it reacts, if interface index changes?

        • Re: Change of SNMP ifIndex
          vhcato

          Tomaz,

          I don't know the exact process by which Orion determines that an interface index changes, but I assume it compares this against some other variable such as "InterfaceName" when it does a rediscovery. Perhaps someone from SW can clarify.

          It's been my experience that when a new interface index is discovered, Orion simply updates the database with the new value, logs it as an event, and continues as normal; mostly. We have seen a number of issues where this process doesn't seem to work correctly if the change is due to a device model change. At times, when we change a device to a different model, we have seen Orion have some difficulties with recognizing the interfaces, even though the names are the same. When this occurs, we generally have to delete and re-add the interfaces.

            • Re: Change of SNMP ifIndex
              BryanBecker

              If this is an issue I know you can use the snmp-server ifindex persist option if your running Cisco IOS. 

              BB

                • Re: Change of SNMP ifIndex
                  tdvojmoc

                  If this is an issue I know you can use the snmp-server ifindex persist option if your running Cisco IOS.
                  It is not an issue yet, but I'll give it some additional test. I'am just noticing some events about interface index changes from no apparent reason.

                • Re: Change of SNMP ifIndex
                  tdvojmoc

                  event, and continues as normal; mostly. We have seen a number of issues where this process doesn't seem to work correctly if the change is due to a device model change. At times, when we change a device to a different model, we have seen Orion have some difficulties with recognizing the interfaces, even though the names are the same. When this occurs, we generally have to delete and re-add the interfaces.
                  Thanks for sharing your experience. Could you please describe your procedure when you are replacing a managed device with a new one, but different model, in more detail? I assume you keep the same management IP and all statistics from before the replacement. Is it just deleting the "unknown" interfaces and adding the new ones?

                  • Re: Change of SNMP ifIndex
                    tdvojmoc

                    We have seen a number of issues where this process doesn't seem to work correctly if the change is due to a device model change.
                    Thanks for sharing your experience. Could you please describe the procedure in NPM when replacing a managed device with different model? I assume your keep the managed IP and the collected statistics from before the replacement. Is it just deleting the "unknown" interfaces, if they appear, and readding the new ones?

                    Edit: Sorry for double posting. I've got an error when I clicked "Post", but it appears, the reply was saved anyway.