Interface index mapping improvements

Document ID : KB000045537
Last Modified Date : 14/02/2018
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NFA version 9.2.1 implements an enhanced renumbering/remapping algorithm to address typical problems that affected earlier versions of the product when device interface is renumbered.


We made some poller remapping improvements from NFA 9.2.1. Interface renumbering (ifIndex changing) was not being handled properly in previous versions of the product. Here are a few scenarios that can cause a device to renumber its interfaces:

  • New line card added
  • Line card removed
  • Line card replacement
  • Device reboot (especially after any of the above changes)

The renumbering/remapping algorithm implemented in 9.2.1 and above considers interfaces to be the same if they have the same ifName and ifDescr but different ifIndex values. The interface map is simply updated with the new ifIndex, along with any other attribute changes. Algorithm improvements include better accounting for removed interfaces, removed routers, ordering in queries, and some improved logging (mostly at warning level).


NFA 9.2.1 and above 


Upgrade to NFA 9.2.1 and above.