Technical Tip: 'Layer-1 and Layer-2 Troubleshooting' with 2 simple commands

[jcovarrubias]

Description	This article describes how to determine if a device is physically connected to the FortiGate and can help detect potential problems with three commands.
Scope	FortiGate.
Solution	Command 1: Identify the available ports with: FortiGate-91G # get hardware nic The following NICs are available: a b lan port1 port2 port3 port4 port5 port6 wan1 wan2 Command 2: diag hardware deviceinfo nic <port>: The information provided confirms if the port is physically connected to an endpoint or networking device and displays negotiation duplex and speed. F1 # diagnose hardware deviceinfo nic port3 Description :FortiASIC NP7LITE Adapter Driver Name :FortiASIC Unified NPU Driver Name :np7lite_0 pid :4 oid :5 vid :6 macid :5 eif_id :7 promiscous :0 mtu :15324 netdev oid :5 dev-flags :1003 dev-promis :0 Current_HWaddr 78:b8:ec:e1:e3:8a Permanent_HWaddr 78:b8:ec:e1:e3:8a ==== Default Link Settings ===== auto-nego :Enable         s_speed :1000        s_duplex :Full       ==== Current Link Settings ===== auto-nego :Enable s_status :Up    <----  UP if the device is connected, this is layer-1. s_speed :1000    --> This shows that if FortiGate cannot negotiate, it will set the speed to 1000mbps. s_duplex :Full   --> This shows that if FortiGate cannot negotiate, it will set duplex to Full. ==== Link Status =============== Admin :Up link_status :Up    <---- UP if the device is connected. Speed :1000       --> This shows the speed that has been negotiated. Duplex :Full       --> This shows if the connection has been negotiated as full-duplex or half-duplex. ==== Netdev Status ============= dev_running :Yes   --> This shows a successful speed/duplex negotiation. dev_carrier :On    <ouput ommited> Command 3: The following command provides valuable information for ports with optical connections. FGT # get system interface transceiver x8 Interface x8 - SFP/SFP+/SFP28, 100GBASE-SR4 or 25GBASE-SR   Diagnostics: Implemented   Vendor Name: FORTINET-ADDON   Part No. : FN-TRANSFP28SRAO   Serial No. : <ommited>   Measurement     Unit Value High Alarm High Warning Low Warning Low Alarm   ------------ ------------ ------------------------ ------------ ------------ ------------   Temperature (Celsius) 36.0   80.0    70.0   0.0   -10.0   Voltage (Volts)       3.31   3.63    3.46   3.13   2.97   Tx Bias (mA)          6.26   15.00   12.00  2.00   1.00   Rx Power (dBm)        -0.6   3.5     3.0   -10.0  -13.0   Tx Power (dBm)         0.7   3.5     3.0   -6.0   -9.0   ++ : high alarm, + : high warning, - : low warning, -- : low alarm, ? : suspect. The first column provides the optical measurements against the following four columns (Minimum/Maximum values) Command 4: 'diagnose user-device-store device memory list': The command applies to ports with LAN roles and device detection enabled.  The command displays the following information. Record #1: device_info 'ipv4_address' = '192.168.1.112' --> If DHCP is not working or a Static IP address is used, this will not show. 'mac' = '78:18:ec:cd:e9:18'  --> MAC information. 'hardware_type' = 'Intel Nuc'  --> Identified device type. 'vdom' = 'root' 'os_name' = 'Debian' 'last_seen' = '1740585358' 'unjoined_forticlient_endpoint' = 'false' 'is_online' = 'true'  'active_start_time' = '1740585361' 'is_fortiguard_src' = 'false' 'purdue_level' = '3' 'max_vuln_level' = 'None' 'total_vuln_count' = '0' 'device_type' = 'Unknown' 'generation' = '2' interface_info 'ipv4_address' = '192.168.1.112' 'mac' = '78:18:ec:cd:e9:18' 'master_mac' = '78:18:ec:cd:e9:18' 'detected_interface' = 'lan' --> Detected Layer 3 Interface/VLAN. 'last_seen' = '1740585358' 'is_master_device' = 'true' 'is_detected_interface_role_wan' = 'false' 'detected_interface_fortitelemetry' = 'true' 'is_online' = 'true' 'is_fortiguard_src' = 'false' Related documents: Troubleshooting Tip: Network Interface Card NIC commands Troubleshooting Tip: SFP transceiver command on a FortiGate