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New Member

Path Analysis (LMS 2.5.1)

Wonder if anyone has ever encountered the problem in Path Analysis (LMS 2.5.1) that layer2 linkage cannot be discovered? The error message I got is:


Error: Hop between and Unable to get the Layer 2 trace between the devices.

Cause: 1)Subnet-to-VLAN mapping table for the devices may be incomplete.

2)Switching path may not be available between the devices.

3)Intermediate device(s) are not in the network, cannot be reached through SNMP, or has not been discovered by the ANI Server.


I am quite sure cause 2 & 3 is invalid. How do I check cause 1? or if there is other reason?


Re: Path Analysis (LMS 2.5.1)

you get access to the Subnet-to-Vlan mapping table through one of the drop down menues at the top of the Path Analysis page.

read the Help to understand what you see. And if you have a configuration on some swithches with voice-vlan and data-vlan on some ports I am sure you wonder about what you see. I think there is another bug.

BTW read the manual (or online help?) for a valid source point and destination point for starting PA. And if PA does not work in one direction (like in your case), just change your source IP with destination IP ... sometimes this helps...


New Member

Re: Path Analysis (LMS 2.5.1)

is there a way to check the other 2 'causes'. Because my subnet-to-vlan is fine. and I thought the other 2 were fine as well but I'm not a 100% sure.