Technical Tip: Changing the speed settings on an interface

[zeeshan_FTNT]

Description

This article explains how to change the speed settings on an interface in order to get the maximum bandwidth on the interface.

Scope

FortiGate.

Solution

Some time speed settings on the public interface do not match with the ISP modem settings.  These settings can be manually adjusted by using the CLI only.

To check the current settings on the public interface:

config system interface
edit wan1
get

If using Vdom:

config vdom

edit root   (where root is the selected vdom)
    config system interface
        edit wan1
get

To change the speed settings to the desired requirement:

config system interface
    edit wan1
        set speed <interface_speed> (10full/10half/100full/100half/1000full/1000half)
    end

The interface speed:

• auto: the default speed. The interface uses auto-negotiation to determine the connection speed.
  
  

Change the speed only if the interface is connected to a device that does not support auto-negotiation:

• 10full — 10 Mbps, full duplex
• 10half — 10 Mbps, half duplex
• 100full — 100 Mbps, full duplex
• 100half — 100 Mbps, half duplex
• 1000full — 1000 Mbps, full duplex
• 1000half — 1000 Mbps, half duplex
  
  

Speed options vary for different models and interfaces.  Enter a space and a '?' after the speed field to display a list of speeds available for the model and interface. The speed cannot be changed for switch interfaces.

Note that the XG2 interfaces on models FortiGate-3140B and FortiGate-3950B cannot be configured for 1000Mbps.

If using VDOM:

config vdom

    edit root   <----- Where root is the selected VDOM.

        config system interface

            edit wan1

                set speed <interface_speed> (10full/10half/100full/100half/1000full/1000half)

             end

Related articles:
Technical Tip: Changing the speed of a FortiGate interface

Technical Tip: Configure Ethernet speed, duplex and negotiation settings.