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Symptom: Intermittent connectivity between two hosts in VLAN 100, but a direct ping works sometimes.
SCT action: Place the terminal in VLAN 100 and run a multicast MAC address listener (e.g., join 01:80:c2:00:00:00). Unexpected BPDUs from VLAN 200? VLAN leak confirmed.
The Subnetwork Craft Terminal is the technician’s scalpel—precise, localized, and essential for the hands-on health of the network. It ensures that even in an era of automation and AI-driven orchestration, human expertise can intervene directly at the hardware layer to build, fix, and optimize the digital infrastructure.
Symptom: VM in VNI 5001 cannot reach gateway. VTEPs show no errors.
SCT action: Deploy an SCT in the overlay subnet (VNI 5001) and send a crafted GARP from a test MAC. Check if the underlay (IP/ UDP) delivers the encapsulated frame. If not, your multicast group or head-end replication list is broken. subnetwork craft terminal
The SCT consists of three functional layers:
It can simultaneously monitor native VLAN, tagged VLANs, and even double-tagged (Q-in-Q) traffic. This is critical for troubleshooting provider bridges or data center fabric edge misconfigurations. Symptom: Intermittent connectivity between two hosts in VLAN
Every action within a Subnetwork Craft Terminal is transactional. The journal maintains a copy of the previous subnet state before each "craft" operation. A single command—craft rollback --last—can revert an entire subnet reconfiguration if a mistake is made.
craft subnet create --cidr 10.10.1.0/24 --draft-mode VLAN leak confirmed
ip link set veth-sub netns subnet_custom
Symptom: Intermittent connectivity between two hosts in VLAN 100, but a direct ping works sometimes.
SCT action: Place the terminal in VLAN 100 and run a multicast MAC address listener (e.g., join 01:80:c2:00:00:00). Unexpected BPDUs from VLAN 200? VLAN leak confirmed.
The Subnetwork Craft Terminal is the technician’s scalpel—precise, localized, and essential for the hands-on health of the network. It ensures that even in an era of automation and AI-driven orchestration, human expertise can intervene directly at the hardware layer to build, fix, and optimize the digital infrastructure.
Symptom: VM in VNI 5001 cannot reach gateway. VTEPs show no errors.
SCT action: Deploy an SCT in the overlay subnet (VNI 5001) and send a crafted GARP from a test MAC. Check if the underlay (IP/ UDP) delivers the encapsulated frame. If not, your multicast group or head-end replication list is broken.
The SCT consists of three functional layers:
It can simultaneously monitor native VLAN, tagged VLANs, and even double-tagged (Q-in-Q) traffic. This is critical for troubleshooting provider bridges or data center fabric edge misconfigurations.
Every action within a Subnetwork Craft Terminal is transactional. The journal maintains a copy of the previous subnet state before each "craft" operation. A single command—craft rollback --last—can revert an entire subnet reconfiguration if a mistake is made.
craft subnet create --cidr 10.10.1.0/24 --draft-mode
ip link set veth-sub netns subnet_custom