3Com 3031 Command Reference Manual page 156

156 C 3: I M C
HAPTER NTERFACE ANAGEMENT OMMANDS
An Ethernet interface on a router that is connected to a hub must work in
half-duplex mode. When an Ethernet interface is connected to a network device
that supports full-duplex, it must work in full-duplex mode, however.
Before setting the FE interface to work in auto-negotiation mode, you must make
sure that the connected remote end has been working in auto-negotiation mode.
If this cannot be guaranteed, the two parties should use the forced setting for the
consistency in operating mode.
For related commands, see speed and display interface.
Example
Set the 100Base-TX FE interface to work in full duplex mode.
[3com-Ethernet0/0/0] duplex full
loopback
Syntax
loopback
undo loopback
View
Ethernet interface view
Parameter
None
Description
Using the loopback command, you can enable an Ethernet interface to perform
loopback. Using the undo loopback command, you can disable loopback.
By default, the Ethernet interface is disabled to perform loopback.
You must enable the Ethernet interface to perform loopback only for the purpose
of testing some special functions.
Example
Enable the Ethernet interface to perform loopback.
[3com-Ethernet0/0/0]loopback
mtu Syntax
mtu size
undo mtu
View
Ethernet interface view