Description | This article describes how to identify if the FortiAP has negotiated ethernet speed and duplex correctly (MDI/MDX). |
Scope | Sometimes there're some physical issues related to the connection between FortiAP and the wired switches. A good way to identify if the FortiAP has negotiated ethernet speed and duplex correctly is via the command line interface which may be accessed directly into the FortiAP shell (SSH) or console and via the FortiGate controller. |
Solution |
The command below can be used directly into the FortiAP CLI to identify the network connection status:
Many parameters may be found, including ethernet port speed, Duplex mode, supported link modes, ethernet flow control (pause frame), etc.
The syntax is as follows:
# ethtool <interface>
It is necessary to change the '<interface>' to inform the LAN port to confirm the status.
Example:
AF-231F # ethtool eth0 Settings for eth0: Supported ports: [ TP AUI BNC MII FIBRE ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Supported pause frame use: Symmetric Receive-only Supports auto-negotiation: Yes Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Advertised pause frame use: Symmetric Receive-only Advertised auto-negotiation: Yes Link partner advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Link partner advertised pause frame use: No Link partner advertised auto-negotiation: Yes Speed: 1000Mb/s Duplex: Full Port: MII PHYAD: 4 Transceiver: external Auto-negotiation: on Link detected: yes
As visible in the output below, FortiAP-231F used in this lab has negotiated correctly the Ethernet Speed to 1000Mb/s and the Duplex is Full Duplex. It can auto-negotiate all these parameters as stated at the beginning of the output with all supported link modes, so it supports MDI/MDX. |
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