cmdb logical relatioship

[Ketan Pandey]

I am working on cmdb ,need advise on this

I have CE router and PE router

LAN Gi1/0 -> CE67676-> WAN GI1/1.554 -> WAN LINK-> Gi1/1/1->KBCN5657->Gi1/1/4(.554)-> 2/2/2->PE24233(2/2/2.554)

CE router CE67676

has interface WAN GI1/1 and sub interface WAN GI1/1.554

PE router PE24233

has interface 2/2/2 and sub interface 2/2/2.554 

PE subinterface is connected to swicth interface Gi1/1/4(.554)

How to store this logical relatiosnhiop in cmdb ,which class i need to use

[AJ-TechTrek]

Hi @Ketan Pandey ,

As per my Understanding Your Network Setup looke like as per below , correct me if i am wrong

* CE Router: CE67676
* Interface: Gi1/1
* Sub-interface: Gi1/1.554 (VLAN 554)
* PE Router: PE24233
* Interface: 2/2/2
* Sub-interface: 2/2/2.554 (VLAN 554)
* Interconnected via:
* Switch KBCN5657
* Interface on switch: Gi1/1/4.554

Recommended CMDB Class Model:

Network Element	CMDB Class
CE/PE Routers	cmdb_ci_network_gear (or subclass like cmdb_ci_router)
Interfaces	cmdb_ci_network_adapter
Sub-interfaces (VLANs)	cmdb_ci_ip_subnet or custom if required
Switch	cmdb_ci_switch
Connections	cmdb_rel_ci or cmdb_ci_ip_connection (for Layer 3)

Steps to Model in CMDB
1. Create CIs:
* CE Router → cmdb_ci_router
* PE Router → cmdb_ci_router
* Switch → cmdb_ci_switch

2. Create Interfaces and Sub-interfaces:
Use cmdb_ci_network_adapter class:
* CE:
* Gi1/1
* Gi1/1.554 (marked as sub-interface, tagged VLAN 554)
* PE:
* 2/2/2
* 2/2/2.554 (marked as sub-interface, tagged VLAN 554)
* Switch:
* Gi1/1/4.554 (connected to PE’s sub-interface)

Use attributes:
* Is Subinterface: true
* Parent Interface: Gi1/1
* VLAN ID: 554

3. Create Relationships:
Use cmdb_rel_ci table for:
* "Connected via" or "Depends on" relationships:
* CE Sub-interface Gi1/1.554 → Switch Interface Gi1/1
* Switch Interface Gi1/1/4.554 → PE Sub-interface 2/2/2.554
Use cmdb_ci_ip_connection for more granular Layer 3 relationships if IP addresses are known.

Notes as per my understanding -
* VLANs can be tracked using cmdb_ci_vlan class if you want to explicitly model 554 as a VLAN object.
* If Layer 2 or Layer 3 topology is critical, consider using Service Mapping or Network Discovery with SNMP/CLI to populate relationships dynamically.
* Maintain ip_address and mac_address attributes in network adapters for mapping accuracy.

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Thank You
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