fix: serial_number handling

[haseebsyed12]

• inspect_hook_node_name_check: use only serial_number field, drop sku fallback
• nautobot_device_sync: set serial_number unconditionally from serial_number field

[stevekeay]

Each server has one "serial number" which appears on a label on the outside of the chassis.

We have always stored this in Nautobot's "serial number" field.

On Dell: the serial number is called a "service tag". It has length 7 and contains characters [0-9A-Z]. (A dell server has many other serial numbers, one for each of it's parts. The long "serial_number" reported in redfish is the serial number of the motherboard, which is not relevant to us.) In the redfish system data, the service tag appears in the "sku" field. Ironic redfish inspection has been copying both "sku" and "serial number" verbatim to the inventory data, and various attempts to fix this have led to some confusion.

On HP: there is a "Server Serial Number" that appears on the chassis, and if memory serves, it appears in the serial number field in redfish. HP serial numbers look like "MXQ622051C".

We don't expect to enrol any HP servers for the time being, but I think we would decide which field to use like if manufacturer contains "dell" then "sku" else "serial_number".

[grizzlydev]

Totally agree, let's not add another field, we should singularly use the thing that appears outside of the chassis, that's the only point - a natural key that spans real world and virtual.

So for Dells we should se the service tag field (whatever that is called in DRAC APIs/ Redfish) into the serial field in Nautobot AND an Ironic node extra{} field called serial

[cardoe]

Ironic redfish inspection has been copying both "sku" and "serial number" verbatim to the inventory data, and various attempts to fix this have led to some confusion.

This was temporary while we worked through the patches upstream. We had pulled the changes in locally before they landed upstream. They are now upstream. There is no sku field in the inventory. It's only "serial number" and has been for a few weeks.

[haseebsyed12]

picked nodes from dev/staging/prod below are the results. explicitly set inspect-interface to idrac-redfish and tested. I see serial number present in inventory after inspect for all these nodes and no sku.

    "system_vendor": {
        "product_name": "PowerEdge R7615 (SKU=0AF7;ModelName=PowerEdge R7615)",
        "serial_number": "4HLWXB4",
        "manufacturer": "Dell Inc.",
        "firmware": {
            "vendor": "Dell Inc.",
            "version": "1.14.1",
            "build_date": "08/08/2025"
        }
    },
    "system_vendor": {
        "product_name": "PowerEdge R7615",
        "serial_number": "4HLWXB4",
        "manufacturer": "Dell Inc.",
        "system_uuid": "4c4c4544-0048-4c10-8057-b4c04f584234"
    },
]

[
    "system_vendor": {
        "product_name": "PowerEdge R7615",
        "serial_number": "MXFC4003C500DH",
        "manufacturer": "Dell Inc.",
        "sku": "DM6PC14",
        "system_uuid": "4c4c4544-004d-3610-8050-c4c04f433134"
    },
    "system_vendor": {
        "product_name": "PowerEdge R7615",
        "serial_number": "DM6PC14",
        "manufacturer": "Dell Inc.",
        "system_uuid": "4c4c4544-004d-3610-8050-c4c04f433134"
    }
]

[
    "system_vendor": {
        "product_name": "PowerEdge R7615 (SKU=0AF7;ModelName=PowerEdge R7615)",
        "serial_number": "GL6PC14",
        "manufacturer": "Dell Inc.",
        "firmware": {
            "vendor": "Dell Inc.",
            "version": "1.6.10",
            "build_date": "12/08/2023"
        }
    }
    "system_vendor": {
        "product_name": "PowerEdge R7615",
        "serial_number": "GL6PC14",
        "manufacturer": "Dell Inc.",
        "system_uuid": "4c4c4544-004c-3610-8050-c7c04f433134"
    },
]

[stevekeay]

We were saying we don't need a custom field, the serial_number field that exists already in nautobot is sufficient for this.

[haseebsyed12]

Tests from Staging

{
    "before": {
        "system_vendor": {
            "product_name": "PowerEdge R7615",
            "serial_number": "CNFCP00375007B",
            "manufacturer": "Dell Inc.",
            "sku": "8Q9PC14",
            "system_uuid": "4c4c4544-0051-3910-8050-b8c04f433134"
        }
    },
    "after_agent": {
        "system_vendor": {
            "product_name": "PowerEdge R7615 (SKU=0AF7;ModelName=PowerEdge R7615)",
            "serial_number": "8Q9PC14",
            "manufacturer": "Dell Inc.",
            "firmware": {
                "vendor": "Dell Inc.",
                "version": "1.6.10",
                "build_date": "12/08/2023"
            }
        }
    },
    "after_redfish": {
        "system_vendor": {
            "product_name": "PowerEdge R7615",
            "serial_number": "8Q9PC14",
            "manufacturer": "Dell Inc.",
            "system_uuid": "4c4c4544-0051-3910-8050-b8c04f433134"
        }
    }
}