Users Guide
• For 100-Gigabit Ethernet interfaces, CR4 auto-negotiation is enabled by default. You cannot enable or disable FEC separately. To enable
or disable FEC, disable CR4 auto-negotiation rst. Similarly, CR4 auto-negotiation cannot be enabled if FEC is already enabled or
disabled. To enable CR4 auto-negotiation, set to default FEC value using the fec default command.
• For 25–Gigabit and 50–Gigabit Ethernet interfaces, FEC is disabled by default. You can enable or disable FEC and CR4 auto-
negotiation simultaneously.
• To view CR4 auto-negotiation and FEC congurations for 25–Gigabit, 50–Gigabit and 100–Gigabit Ethernet interfaces, use the show
interfaces command.
Dell#show interfaces hundredGigE 1/1/3
hundredGigE 1/1/3 is up, line protocol is up
Hardware is DellEth, address is 4c:76:25:e5:fb:40
Current address is 4c:76:25:e5:fb:40
Pluggable media present, QSFP28 type is 100GBASE-SR4
AutoNegotiation is OFF
Forward Error Correction(FEC) is ON
Wavelength is 850nm
QSFP28 receive power reading is -0.1950dBm
Interface index is 2098189
Internet address is not set
Mode of IPv4 Address Assignment : NONE
DHCP Client-ID :4c7625e5fb40
MTU 1554 bytes, IP MTU 1500 bytes
LineSpeed 100000 Mbit
Flowcontrol rx off tx off
ARP type: ARPA, ARP Timeout 04:00:00
Last clearing of "show interface" counters 03:02:45
Queueing strategy: fifo
Input Statistics:
356 packets, 22784 bytes
356 64-byte pkts, 0 over 64-byte pkts, 0 over 127-byte pkts
0 over 255-byte pkts, 0 over 511-byte pkts, 0 over 1023-byte pkts
356 Multicasts, 0 Broadcasts, 0 Unicasts
0 runts, 0 giants, 0 throttles
0 CRC, 0 overrun, 0 discarded
Output Statistics:
356 packets, 22784 bytes, 0 underruns
356 64-byte pkts, 0 over 64-byte pkts, 0 over 127-byte pkts
0 over 255-byte pkts, 0 over 511-byte pkts, 0 over 1023-byte pkts
356 Multicasts, 0 Broadcasts, 0 Unicasts
0 throttles, 0 discarded, 0 collisions, 0 wreddrops
Rate info (interval 299 seconds):
Input 00.00 Mbits/sec, 0 packets/sec, 0.00% of line-rate
Output 00.00 Mbits/sec, 0 packets/sec, 0.00% of line-rate
Time since last interface status change: 03:01:47
Setting the Speed and Duplex Mode of Ethernet
Interfaces
To discover whether the remote and local interface requires manual speed synchronization, and to manually synchronize them if necessary,
use the following command sequence.
1 Determine the local interface status. Refer to the following example.
EXEC Privilege mode
show interfaces [interface | stack—unit stack-unit-number] status
2 Determine the remote interface status.
EXEC mode or EXEC Privilege mode
[Use the command on the remote system that is equivalent to the rst command.]
3 Access CONFIGURATION mode.
EXEC Privilege mode
config
Interfaces
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