Mixed IPv4 and IPv6 elinks are mis-labeled as lans

[Morten Brekkevold]

In environments with mixed IPv4 and IPv6 prefixes on link and elink networks, ipdevpoll will sometimes be unable to label it as such, and may mis-label it as a lan network.

Specifically in the case of an elink, the net type selection algorithm is dependent on the small subnet sizes used for such networks with IPv4. A link network would typically have a /30 mask with IPv4, but if the network also carries IPv6 traffic, the convention is to use /64 networks (which you would for almost any IPv6 subnet).

The algorithm picks one of the prefixes attached to the vlan/broadcast domain and selects net type based on this. The selected prefix is entirely dependent on Pythons ordering of dictionary keys, which is not reliable. IPv4 prefixes should be prioritized, since their netmasks carry more information.

[Morten Brekkevold (mbrekkevold)]

fix here: http://nav.uninett.no/hg/stable/rev/7bc8419e480e