Dependency View for Switches (Core, Distribution, Access)

[FriendlyDude]

Hi All,

In Dependency View of a core switch, I'm able to see connected devices top to bottom and bottom to top. But when I open dependency view of an access switch from the core switch I'm viewing, I'm just seeing top to bottom but no bottom to top connections.

In the form view of the core switch, I can see there are downstream relationships including access switches as well as upstream relationship to an esx server. However, when I visit the form view of an access switch coming from the core switch, there are only downstream relationships, but no upstream relationship pointing to the core switch.

Why is this happening?

One more thing I would like to ask, would it be possible to exclude unwanted ports in dependency view? Let's say my switch contain 48 ports and each port is being discovered and can be seen in the related items of a switch. These 48 ports are showing in the dependency view even if it is not being used and could make the dependency view look cluttered, so I'm wondering if it would be possible to exclude unwanted ports.

Thanks!

[AJ-TechTrek]

Hi @FriendlyDude ,

As per my understanding this is typically happens due to missing or incomplete relationship records in the CMDB.
* In ServiceNow Dependency Views, the arrows are drawn based on cmdb_rel_ci records.
* If the access switch only shows downstream relationships, it means Discovery created relationships like “Access Switch → Connected Device”, but the reverse/upstream “Core Switch → Access Switch” was not discovered.

Solution Approach:
* Check cmdb_rel_ci table for the access switch → do you see an Upstream relationship pointing back to the core switch? If not, Discovery hasn’t created it.
* Review the SNMP credentials & OIDs being polled for both devices — uplink discovery depends on proper interface data.
* If Discovery pattern doesn’t capture uplink relationships well, you may need to extend the Network Switch Pattern to populate the upstream side.

2. Excluding unwanted ports (48 discovered ports cluttering dependency view)
This is a known issue when switches with many interfaces are discovered. By default, Discovery creates CIs for every port/interface, even if unused.

Solution - 1. Filter relationships in Dependency View Rules:
* Navigate to Dependency Views → View Rules.
* Create a filter to exclude certain CI classes or attributes (e.g., exclude cmdb_ci_network_adapter where oper_status=down).
* This way, unused ports will not appear in the map.

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Thank You
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