Interface Configuration
7750 SR OS Interface Configuration Guide Page 331
• “limited” where a single speed/duplex is advertised. 
When autonegotiation is enabled on a port, the link attempts to automatically negotiate the link speed 
and duplex parameters. If autonegotiation is enabled, the configured duplex and speed parameters are 
ignored. 
When autonegotiation is disabled on a port, the port does not attempt to autonegotiate and will only 
operate at the speed and duplex settings configured for the port. Note that disabling autonegotiation 
on gigabit ports is not allowed as the IEEE 802.3 specification for gigabit Ethernet requires 
autonegotiation be enabled for far end fault indication.
If the autonegotiate limited keyword option is specified the port will autonegotate but will only 
advertise a specific speed and duplex. The speed and duplex advertised are the speed and duplex 
settings configured for the port. One use for limited mode is for multispeed gigabit ports to force 
gigabit operation while keeping autonegotiation enabled for compliance with IEEE 801.3.
7750 SR OS requires that autonegotiation be disabled or limited for ports in a Link Aggregation 
Group to guarantee a specific port speed.
The no form of this command disables autonegotiation on this port.
Default autonegotiate
Parameters limited — The Ethernet interface will automatically negotiate link parameters with the far end, but 
will only advertise the speed and duplex mode specified by the Ethernet speed and duplex 
commands.
dot1q-etype
Syntax dot1q-etype 0x0600..0xffff
no dot1q-etype
Context config>port>ethernet
Description This command specifies the Ethertype expected when the port's encapsualtion type is dot1q. Dot1q 
encapsulation is supported only on Ethernet interfaces.
The no form of this command reverts the dot1q-etype value to the default.
Parameters 0x0600..0xffff — Specifies the Ethertype to expect.
Default If the encap-type is dot1p, then the default is 0x8100.
If the encap-type is qinq, then the default is 0x8100.
duplex
Syntax duplex {full | half}
Context config>port>ethernet
Description This command configures the duplex of a Fast Ethernet port when autonegotiation is disabled.