Interface called ifIndex0 on non-snmp router?

Hi,

For various reasons, I can't use SNMP with NFA for two of my routers. I've edited all the interface descriptions manually to get around this.

However, there's a bit of an oddity here. In the netflow_interface table in the database, there's an interface whose snmp_description is IfIndex0 in addition to all the others. This interface doesn't show up in the web interface.

The problem is that in the netflowraw_blahblahblah tables, there are rows whose dst_if references the IfIndex0 interface described above - this means that none of this traffic is accounted.

What's going on? What are the IfIndex0 interfaces in the database for?

many thanks,
alec