How to read z-wave topology

My z-vawe topology makes very little sense to me and has been from the time I started with Hubitat. For example the Main Valve Node 06 in the table shows route directly to the Hub. 01->06 but the topology picture shows the connection to 1A.
1A is in the kitchen at the opposite corner of the house with a lot ( about 4) repeater nodes in between. Still none of those nodes is shown connected directly to the hub. All of the repeater devices with exception of the valve (6) are from the same manufacturer Z-Link temperature and water sensors)
I tried to repair z-wave several times but it stays the same. i.e. the topology never shows exactly the same routes as in the table.
Is this expected ?

The two info dumps are different. The Zwave Details is "Live when displayed, but not self-refreshed" while the Topology Map is old in comparison. In an hour, it might look different, is what I'm saying.

Zwave Details is read from the ZWave Radio's SDK at the time the page is displayed. It is the best display of what's out on the radio DB.

I don't remember the schedule that the Topology map is refreshed, but it is something in the hourly range I vaguely recall. It seems like you're reading it right, even if it leads you astray. :smiley:

Well, it has not refreshed in a year, should I give it more time ? :slight_smile:

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Nope, that should be adequate :smiley:

What does the rest of your z-wave details page look like? (Post it in it's entirety) Easier to tell health that way.

I am not very comfortable posting my whole network here. I am also not sure about the previous explanation about topology caching. Z-wave details have all the information to build the topology map, there is no need to cache anything. These kind of tasks are often asked at job interviews, and take no more than one hour to solve. I think it is a bug.

There isn't anything personally identifiable in z-wave. A lot of post for diagnostics.

But yours doesn't match anyone else's -- your hub is the only one exhibiting this behavior. I have 3 hubs that have a ZWave mesh and all 3 display "correctly."

I removed the stuff I do not want to share ( confirmed that the topology is as it was before) and here is my complete topology. As you see from the route column many devices connect to the hub via Main Valve (06) But the topology shows that the Main Valve is not connected to the hub directly.
I marked the repeater devices with red circle, others are battery powered devices.
Besides that the routing looks far from optimal for most devices. Water heater for example is literally next to the Main Valve ( Both are in the garage) but it is connected to the Master Bathroom ( device 15) which is the farthest of all devices on a different floor and three rooms away and then finds a long route back to the hub.


I think it is a definition of a bug :slight_smile:

If I could ask for an explanation.
Are the white diagonal squares that go from top left to bottom right indicating the connectivity point for the controller for any of these devices? I see a common theme with each device, such as 15 in this Topo, the X and Y axis converge to the Controller at the white diagonal square. Is that correct or not?
Each Mains AC device has red and blue squares outward from the center where the device 'meets' itself. What's the significance of the colors?

One axis is "Hub to Device". The other Axis is "Device to Hub"

Ideally both axis match. A mismatch means that either the hub can't talk to the device or the device can't talk to the Hub. That better explains the white middle diagonal.. it's a "self to self" point in the chart.

The indicators come from Polling the devices.. the hub asks. "who are my neighbors? (who can hear this?)" Then the hub asks all the nodes to send their own neighbor list. An individual node might get this second query via a neighbor, and send the list of neighbors back the same way.

The Topology table is just a visual display of those answers.

Screenshot 2023-03-13 at 11.29.53 AM
This is the simplest Topology I can find, it says the hub can be heard by the device and the device can hear the Hub. The hub sent out a query asking for neighbors, and only one device answered. Then it sent out a mesh wide broadcast asking for each device to respond with their unique list of neighbors. One set of answers goes in one axis, the other set of answers goes in the opposite axis.

This topology shows that every device can hear the Hub (except one) and every device has the hub as a neighbor (except one). There's a problem with the 2nd device #9 in that it has only one neighbor, device 61. If that device has a fault, then I also lose device #9.

Does that help?

A critical element is that the queries for a list of neighbors is NOT run when you click the Topology Map button. It might have been run a week ago. In my example above, that #9 device is a strip of RGBW LEDs stuck to the upper edge of my kid's Computer Monitor. It was used during Covid and Zoom Classroom days. They used to automatically light when school started and go off when it was done. Doesn't happen any more AND the wall wart has long ago fallen off the wall. The device is a Ghost in the classic sense, although plugging it back in would probably restore it.

Yes, very helpful. I notice that device 61 is red and all of the others on the top and left side axis are blue. Does that mean that 61 is a failed node?
Do ghosts nodes ever show in a Topology?

61 is not a failed node. Node 9 is the interesting node.. if you put your finger on node 9 on the left column, then run across to a Blue then down 3.. you'll be on node 28 then look on the left... which HAS a blue on column 1. Same with node 38 and 54. They all have blue squares in the vertical 61 column AND they all have blue in the left most node 1 column. That means any of the 3 can be a path back to the Hub.

Said another way, node 1, the hub, can converse with nodes 28, 38 or 54 in order to converse with node 61 and node 61 can converse with node 9. And Node 9 can follow any of those paths back. But MUST go through 61.

A ZWave Details page might show any of these:

  • 01 -> 28 -> 61 -> 9 100kbps
  • 01 -> 38 -> 61 -> 9 100kbps
  • 01 -> 54 -> 61 -> 9 100kbps

I should mention that the responses back from devices when asked for neighbors includes the quality, so the hub, which is what decides the actual routes.

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I would concern myself less with the toplogy map then with the routing column...Though the topology map shows that the valve is connected directly. Overall your mesh looks fine. You do have some high hops but by the looks of things your devices are spread out. Your valve is directly connected to your hub. z-wave is gonna route the way it wants to route. You can try individual node repairs but likely not much will happen. Going to a c8 with a mesh like yours would really improve things. Also side note: No identifying stuff on that page outside of the brand/type of device.