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Staff & Editor
Staff & Editor
Oct 11, 2024 5:03 AM UTC

Technical Tip: 4x100G Split Mode Interface Does Not Display the Correct Speed

Description This article provides a solution for an issue where the interface media type is incorrectly displayed when configuring a 4x100G split-port mode on FortiGates.
Scope FortiGates supporting split port functionality and running v7.2.8.
Solution
When a split port is configured on a port, 50G interface speed is seen instead of 100G in the interface media-type output.
 
config split-port-mode
    edit "port25"
        set split-mode 4x100G
    next
end
 
get sys interface media-type port25/1
port25/1 : 50G-Fiber-multi_interface
 
get sys interface media-type port25/2
port25/2 : 50G-Fiber-multi_interface
 
get sys interface media-type port25/3
port25/3 : 50G-Fiber-multi_interface
 
get sys interface media-type port25/4
port25/4 : 50G-Fiber-multi_interface
 
The correct speed is seen in the below outputs:
 
show system interface port24/1
config system interface
    edit "port25/1"
        set vdom "3py"
        set type physical
        set snmp-index 55
        set speed 100Gfull
        set mediatype sr2
        set forward-error-correction cl91-rs-fec
    next
end
 
get sys interface physical port24/1
== [onboard]
        ==[port25/1]
                mode: static
                ip: 0.0.0.0 0.0.0.0
                ipv6: ::/0
                status: up
                speed: 100000Mbps (Duplex: full)
                FEC: cl91-rs-fec
                FEC_cap: {disable}
 
This is just a media-type display issue and does not impact the port functionality.
 
The issue has been resolved in FortiOS version 7.6.1.
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