Virtual status of router addresses cycles back and forth, causing net type to swing back and forth between lan and link

[Morten Brekkevold]

As observed by a customer, on an HSRP-enabled subnet, the net type categorization NAV makes for the subnet swings back and forth between "lan" and "link". The correct type is of course "lan".

A code inspection of the ipdevpoll virtualrouter plugin reveals that it will set the virtual status of all router addresses based on the output of first one MIB, then do the same for all router addresses based on the output of another MIB.

The two MIBs are CISCO-HSRP-MIB and VRRP-MIB. If virtual addresses are found using HSRP first, and no results are found in VRRP after that, the VRRP results will wipe out the changes made because of the HSRP results.

The order in which the MIBs are queried is not deterministic, due to the way dictionary hashing works in Python, causing the address status and network type to swing back and forth.

[Morten Brekkevold (mbrekkevold)]

fix here: https://nav.uninett.no/hg/stable/rev/d33ac3bdf37e