Problem with cable trace system

Environment

• Python version: Python 3.7.3
• NetBox version: 2.10.4

Steps to Reproduce

1. Insert all objects(via Import)

Manufacturers

name,slug
Unknown,unknown

Sites

name,slug
UNKNOWN,unknown

Racks

site,group,name,facility_id,tenant,status,role,type,serial,asset_tag,width,u_height,desc_units,outer_width,outer_depth,outer_unit,comments
UNKNOWN,,test_rack,,,active,,,,,19,42,,,,,

Device Types

manufacturer: Unknown
model: INTERFACE-DUPLEX
slug: interface-duplex
part_number: ''
u_height: 0
is_full_depth: false
subdevice_role: ''
comments: ''
front-ports:
- name: Fiber 1
  type: sc
  rear_port: output
  rear_port_position: 1
- name: Fiber 2
  type: sc
  rear_port: output
  rear_port_position: 2
rear-ports:
- name: output
  type: lc
  positions: 2
---
manufacturer: Unknown
model: Router
slug: router
part_number: ''
u_height: 1
is_full_depth: true
subdevice_role: ''
comments: ''
interfaces:
- name: SFP+1
  type: 10gbase-x-sfpp
  mgmt_only: false
---
manufacturer: Unknown
model: PatchPannel
slug: patchpannel
part_number: ''
u_height: 1
is_full_depth: true
subdevice_role: ''
comments: ''
front-ports:
- name: A1
  type: lc
  rear_port: output
  rear_port_position: 1
- name: A2
  type: lc
  rear_port: output
  rear_port_position: 2
- name: A3
  type: lc
  rear_port: output
  rear_port_position: 3
- name: A4
  type: lc
  rear_port: output
  rear_port_position: 4
- name: A5
  type: lc
  rear_port: output
  rear_port_position: 5
- name: A6
  type: lc
  rear_port: output
  rear_port_position: 6
- name: A7
  type: lc
  rear_port: output
  rear_port_position: 7
- name: A8
  type: lc
  rear_port: output
  rear_port_position: 8
- name: A9
  type: lc
  rear_port: output
  rear_port_position: 9
- name: A10
  type: lc
  rear_port: output
  rear_port_position: 10
- name: A11
  type: lc
  rear_port: output
  rear_port_position: 11
- name: A12
  type: lc
  rear_port: output
  rear_port_position: 12
rear-ports:
- name: output
  type: sc
  positions: 12

Device Roles

name,slug,color,vm_role,description
UNKNOW,unknow,9e9e9e,,

Devices

name,device_role,tenant,manufacturer,device_type,platform,serial,asset_tag,status,site,rack,position,face,comments
PatchPannel A-Side,UNKNOW,,Unknown,PatchPannel,,,,active,UNKNOWN,test_rack,3,front,
PatchPannel Z-Side,UNKNOW,,Unknown,PatchPannel,,,,active,UNKNOWN,test_rack,2,front,
Router A-Side,UNKNOW,,Unknown,Router,,,,active,UNKNOWN,test_rack,4,front,
Router Z-side,UNKNOW,,Unknown,Router,,,,active,UNKNOWN,test_rack,1,front,
INTERFACE-DUPLEX A-Side,UNKNOW,,Unknown,INTERFACE-DUPLEX,,,,active,UNKNOWN,test_rack,,,
INTERFACE-DUPLEX Z-Side,UNKNOW,,Unknown,INTERFACE-DUPLEX,,,,active,UNKNOWN,test_rack,,,

Cables

side_a_device,side_a_type,side_a_name,side_b_device,side_b_type,side_b_name
Router A-Side,dcim.interface,SFP+1,INTERFACE-DUPLEX A-Side,dcim.rearport,output
INTERFACE-DUPLEX A-Side,dcim.frontport,Fiber 1,PatchPannel A-Side,dcim.frontport,A1
INTERFACE-DUPLEX A-Side,dcim.frontport,Fiber 2,PatchPannel A-Side,dcim.frontport,A2
PatchPannel A-Side,dcim.rearport,output,PatchPannel Z-Side,dcim.rearport,output
INTERFACE-DUPLEX Z-Side,dcim.frontport,Fiber 2,PatchPannel Z-Side,dcim.frontport,A1
INTERFACE-DUPLEX Z-Side,dcim.frontport,Fiber 1,PatchPannel Z-Side,dcim.frontport,A2
Router Z-side,dcim.interface,SFP+1,INTERFACE-DUPLEX Z-Side,dcim.rearport,output

1. Try to follow SFP+1 of “Router A-Side”, you get this :

2. Click on “Fiber 1”

Expected Behavior

Show the cable trace following “Fiber 1”

Observed Behavior

I try to use :

./manage.py trace_paths
# and
./manage.py trace_paths --force

without any changes

[jeremystretch]

To be clear, it never handled modeling optics as part of the tracing logic.

[xkilian]

(corrected, incorrectly inserted something about optics) Maybe after 2.11 it might be interesting to revisit this issue at the root to see if the core model could be improved or how the tracing could be improved to handle Y types and different other useful cases without causing bugs/issues/problems/maintainability issues with the cable tracing logic. I have read through the various threads. I am also involved/responsible with an in-house product that does this at large scale, so this is a topic dear to me. Jeremy has been clear that at this point it is not part of the current product and the tracing logic has been changed, that it no longer handles that use case ( Y connexions) and tracing through circuits.