Administrator Guide

The local interface and the directly connected remote interface must have the same setting, and auto-
negotiation is the easiest way to accomplish that, as long as the remote interface is capable of auto-
negotiation.
NOTE: As a best practice, Dell Networking recommends keeping auto-negotiation enabled. Only
disable auto-negotiation on switch ports that attach to devices not capable of supporting
negotiation or where connectivity issues arise from interoperability issues.
For 10/100/1000 Ethernet interfaces, the negotiation auto command is tied to the speed command.
Auto-negotiation is always enabled when the speed command is set to 1000 or auto.
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 | linecard slot-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 first command.]
3. Access CONFIGURATION mode.
EXEC Privilege mode
config
4. Access the port.
CONFIGURATION mode
interface interface slot/port
5. Set the local port speed.
INTERFACE mode
speed {10 | 100 | 1000 | auto}
6. Optionally, set full- or half-duplex.
INTERFACE mode
duplex {half | full}
7. Disable auto-negotiation on the port.
INTERFACE mode
no negotiation auto
If the speed was set to 1000, do not disable auto-negotiation.
8. Verify configuration changes.
INTERFACE mode
show config
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Interfaces