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For non Dell-qualified SFP28 optics:
Aug 8 20:31:56 %Z9100-ON:1 %IFAGT-5-UNSUP_OPTICS: Non-qualified optics in slot 1 port
7/1. Wrong QSA in use. Please utilize QSA28, not lower speed QSA to guarantee support
and performance for 25G Optics and cables
FEC Configuration
FEC configurations are available on 100Gigbit, 50Gigabit and 25Gigabit Ethernet interfaces.
To configure FEC, use the following commands.
Enable FEC.
INTERFACE mode
fec enable
The CL91 keyword enables RS-FEC on 100G interfaces as per IEEE. The system displays an error message when this is
applied on 25G or 50G interfaces.
The CL74 keyword enables BaseR-FEC on 25G or 50G interfaces as per 25G/50G Ethernet Consortium. The system
displays an error message when this is applied on 100G interfaces.
To disable FEC, use the no fec enable command.
Set to default FEC value.
INTERFACE mode
fec default
Verify the configuration.
INTERFACE mode
show config
example for the fec enable command for a 100G interface.
DellEMC(conf-if-hu-1/1)#fec enable
DellEMC(conf-if-hu-1/1)#show config
!
interface hundredGigE 1/1
no ip address
shutdown
intf-type cr4 autoneg
fec enable
Important Points to Remember
For 10Gigabit and 40Gigabit Ethernet interfaces, FEC configurations are not applicable.
For 100-Gigabit Ethernet interfaces, CR4 auto-negotiation is enabled by default. You can enable or disable FEC and auto
negotiation irrespective of each other.
For 25Gigabit and 50Gigabit Ethernet interfaces, FEC is disabled by default. You can enable or disable FEC and CR4
auto-negotiation simultaneously.
To view auto-negotiation and FEC configurations for 25Gigabit, 50Gigabit and 100Gigabit Ethernet interfaces, use the
show interfaces command.
If you connect the 25G SR optics between the S5048-ON and Z9100, enable FEC CL74 on S5048-ON for the link to come
up.
DellEMC#show interfaces hundredGigE 1/10
hundredGigE 1/10 is up, line protocol is up
Hardware is DellEMCEth, address is 00:12:32:12:42:13
Current address is 00:12:32:12:42:13
Pluggable media present, QSFP28 type is 100GBASE-CR4-3M
AutoNegotiation is OFF
Forward Error Correction(FEC) configured is cl91 (RS-FEC)
Wavelength is 64nm
Interface index is 2101774
Internet address is not set
Mode of IPv4 Address Assignment : NONE
DHCP Client-ID :001232124213
Interfaces
395