Re: Problem with uplink detecion
On Thu, 10 Apr 2014 12:00:24 +0000 "martin.jaburek@..."
> I can understand, that it is trying to determine the topology based on
> How do you handle the situation when we have many vlans with different STP
> roots? Or some uplinks are limited to a subset of available vlans.
NAV will traverse the path of each VLAN individually, starting at the
determined root router port for that VLAN. NAV does not get root
information from STP, but has detected which subnet prefix(es) are
routed on that VLAN, and uses this to detect the root router port.
On the device connected to that router port (or on the same device, in
the case of an L3 switch), NAV will descend further on all trunks with
the current VLAN allowed, and non-trunks having this as their native
STP information is only used to find STP blocked ports. STP blocked
ports will not be traversed by the detector, only registered as blocked
on the VLAN that is being detected.
> Or if we have different allowed vlans from one side and the other
You mean a mismatch in the list of allowed vlans on each side of a
trunk? That would be logged as an error.
> I attached navtopology.log. I reduced it to include only three devices
> oriented messages.
> They are connected:
> DEVICE_003 Te0/1 (role: vlan492 ... ROOT, vlan25 ... ROOT) <-> DEVICE_009
> Te2/2 (role: vlan492 ... DESG, vlan25 ... DESG)
> DEVICE_003 Gi0/24 (role: vlan492 ... DESG, vlan25 ... DESG) <-> DEVICE_001
> Gi1/0/9 (role: vlan492 ... ALTN, vlan25 ... ALTN)
> DEVICE_009 and DEVICE_001 are then connected through other switches.
> On webinterface ipdevinfo/DEVICE_003 there are N/A uplinks.
Do you mean to say there are _no_ uplinks listed whatsoever, or that
there are uplinks where the port name is unavailable?
> I'm not sure about rules you apply for uplink detection, maybe the log will
What is the actual uplink of DEVICE_003?
According to your log, most VLANs are attempted traced through Gi0/24 on
DEVICE_003, but most of them seem to be STP blocked on this port.
If this is the actual uplink, but it is STP blocked on all VLANs, NAV
will not set a direction for the port/VLAN combination, it will set the
port/VLAN combination as blocked. If there is no information about
directionality of the link, nothing will be listed in the uplinks list.