Loopback - 3Com 8807 Command Reference Manual

Ethernet Port Configuration Commands 139
Description
Use the jumboframe enable command to permit jumbo frames to pass the card
on the specified slot and set the maximum size of Jumbo frames.
Use the jumboframe disable slot command to prohibit jumbo frames from
passing the card on the specified slot.
By default, jumbo frame is permitted to pass cards.
Related command: display jumboframe configuration.
n
The system supports discrete values of Jumbo frame lengths ranging from 1536 to
10240. However, effective Jumbo frame values fall into several sections: the
effective Jumbo frame value for the 1536-1552 section is 1552, that for the
1553-9022 section is 9022, that for the 9023-9192 section is 9192, and that for
the 9193-10240 section is 10240.
Example
# Permit jumbo frames to pass the card on slot 6 and set the maximum size of
Jumbo frames to 9022 .
<SW8800>system-view
[SW8800] jumboframe enable 9022 slot 6

loopback

Syntax
loopback { external | internal }
undo loopback
View
Ethernet port view
Parameter
external: Ethernet port in external loop mode. Presently, the Ethernet ports of the
3Com Switch 8800 Family Series Routing Switches do not support this mode.
internal: Ethernet port in internal loop mode.
Description
Use the loopback command to set the Ethernet port in loop mode.
Use the undo loopback command to cancel the loop setting.
By default, the Ethernet port is not in loop mode.
Example
# Configure Ethernet2/1/1 in internal loop mode.
<SW8800>system-view
System View: return to User View with Ctrl+Z.
[SW8800]interface ethernet2/1/1
[3Com-Ethernet2/1/1] loopback internal