Netforge.ai Docs
Open the app →
Docs/Guide/Device Configuration/Interfaces

Interfaces

Physical port settings — set device-wide defaults, override per interface.

Relevant for:Professional ServicesEnterprise / NetOps

The Interfaces tab configures the physical layer of every port on the device. Set a device-wide default profile once (applied to all connected ports), then add per-interface overrides only where a port differs — the generated configuration merges the two, and each vendor template renders its own CLI dialect.

Speed, duplex & MTU#

Where to find itCanvasSelect a deviceInterfaces tabPort Defaults / per-interface override

Pick a fixed speed (10 Mbps – 100 Gbps) and duplex, or leave them onauto. Setting Negotiation to manual disables auto-negotiation entirely — required on some carrier hand-offs. MTU raises the frame size for jumbo traffic, and load-interval shortens the window used to compute the interface throughput counters.

Why
Fixing speed/duplex on both ends of a link prevents a duplex mismatch — the classic silent killer where auto on one side and fixed on the other negotiates half-duplex and causes late collisions and abysmal throughput. Jumbo MTU (9216) avoids fragmentation for VXLAN/overlay, storage, and vMotion traffic. A 30-second load-interval makes utilization graphs and show interface rates react ~10× faster than the 5-minute default, which matters when you are chasing microbursts.
interface GigabitEthernet0/0/1
 description to access-sw-01
 no negotiation auto
 speed 1000
 duplex full
 mtu 9216
 load-interval 30
Important
MTU ceilings differ per platform — NX-OS and IOS-XE accept up to 9216, Arista EOS up to 9214. Options a platform cannot render directly are omitted from its config, and the Validate drawer warns you (for example, negotiation control is not configurable on ArubaOS-CX).

Feature bindings & per-port hardening#

Bind named objects from the Features tab per port — an ACL (aclIn/Out), a NetFlow monitor, a QoS service-policy or trust state — and control discovery protocols per interface. Storm control and port security round out access-port hardening.

Why
Per-port CDP/LLDP control matters at trust boundaries: keep discovery on inside the network for operations, disable it on internet- and partner-facing ports where it leaks device models and addressing. QoS trust dscp belongs on ports facing devices that mark correctly (APs, servers) — untrusted ports get re-marked.
interface GigabitEthernet1/0/1
 description to user-port
 switchport mode access
 spanning-tree portfast
 ip access-group EDGE-IN in
 ip flow monitor NF input
 mls qos trust dscp
 no cdp enable
 lldp transmit
 lldp receive
Note
Validation cross-checks every binding: an interface referencing an ACL or flow monitor that is not defined in Features is flagged before generation.