linkd can't make use of learned MAC addresses on ports to determine path mapping

Description

OpenNMS, via linkd, can't seem to figure out the path relations between a good number of the switches on my network [of the Cisco, Dell, and Arista varieties] and the endpoint devices - at least for the Arista and Dell cases, it's certainly possible to associate this topological information by mapping the MAC of an endpoint device across the network using e.g. Q-BRIDGE-MIB::dot1qTpFdbStatus on the different switches, along with the STP and port status to enumerate a path relationship to the given device(s).

I tried this in a constrained environment by handing linkd an explicit enumeration of a dozen devices, to ensure rapid runtime - all but one of the switches on the path between two of the three endpoint devices (Arista DCS-7140T-8S, a few Dell 2816s, a Dell 6248, a Cisco 2960 stack, and a Cisco Nexus 7000-series), two switches not in that path, and 3 endpoint devices. OpenNMS enumerated all the relevant devices and failed to find any path information between any of them.

If it may be necessary, I can write such a thing [though I realize that the combinatoric explosion innate to the description involved may cause the memory usage to exceed most people's desired use case], but I'm genuinely surprised this is not existing functionality...

Environment

CentOS 6

Acceptance / Success Criteria

None

Lucidchart Diagrams

Activity

Show:

Antonio Russo March 16, 2015 at 12:07 PM

There is not enough data to worlk this.
Please attach the walks and reopen when done.

Antonio Russo March 3, 2015 at 4:19 AM

This should be fixed in Enhanced Linkd.
Could you provide some walks so that we can test the env?

Just a couple of walks of the mib2 tree to check if we have some issues.

snmpwalk -c <communivty> -v2c -Oune <ip address> .1.3.6.1.2.1

If you have lldp enable you should also walk the lldp data...

snmpwalk -c <communivty> -v2c -Oune <ip address> .1.0.8802.1.1.2

And finally if you have CDP enabled you should walk the cdp cache information too....

snmpwalk -c <communivty> -v2c -Oune <ip address> .1.3.6.1.4.1.9.9.23

Seth Leger January 21, 2015 at 11:04 PM

Is this handled in the new Enlinkd code?

Incomplete

Details

Assignee

Reporter

Components

Fix versions

Affects versions

Priority

PagerDuty

Created June 5, 2014 at 3:40 AM
Updated May 11, 2015 at 3:50 PM
Resolved March 16, 2015 at 12:07 PM