HP A5120 EI Series Configuration Guide

11
To do…
Use the command…
Remarks
or port group
view
Enter port
group view
To configure jumbo frame support on one
Ethernet interface, enter Ethernet interface
view.
To configure jumbo frame support on a
group of Ethernet interfaces, enter port
group view.
Enable the interface to accept
jumbo frames
jumboframe enable
Required
By default, an Ethernet interface accepts
jumbo frames (up to 9216 bytes).
Enabling single-port loopback detection on an Ethernet
interface
If an interface receives a packet that it sent, a loop occurs. Loops might cause broadcast storms,
degrading network performance. You can use loopback detection to detect loops on an interface and
configure the protective action to take on the interface when a loop is detected, for example, to shut
down the interface. In addition to the configured protective action, the switch also performs other actions
to alleviate the impact of the loop condition, as described in Table 1.
Table 1 Actions to take upon detection of a loop condition
Port type
Actions
No protective action is configured
A protective action is configured
Access interface
 Put the interface in controlled mode.
The interface discards all incoming
packets, but still forwards outgoing
traffic.
 Create traps.
 Delete all MAC address entries of
the interface.
 Perform the configured protective
action.
 Create traps and log messages.
 Delete all MAC address entries of the
interface.
Hybrid or trunk
interface
 Create traps.
 If loopback detection control is
enabled, set the interface in
controlled mode. The interface
discards all incoming packets, but
still forwards outgoing packets.
 Delete all MAC address entries of
the interface.
 Create traps and log messages.
 If loopback detection control is
enabled, take the configured
protective action on the interface.
 Delete all MAC address entries of the
interface.
Follow these steps to configure single-port loopback detection:
To do…
Use the command…
Remarks
Enter system view
system-view
—
Enable global loopback detection
loopback-detection enable
Required
Disabled by default.
Set the loopback detection
interval
loopback-detection interval-time
time
Optional
30 seconds by default.

HP A5120 EI Series Specifications

General

Uplink Ports	4 x SFP
Stacking	No
Management	CLI, Web, SNMP
Routing Protocols	RIP, OSPF
Power Supply	AC
MAC Address Table Size	16K
Dimensions	440 x 430 x 44 mm
Operating Temperature	0°C to 45°C
Operating Humidity	10% to 90% non-condensing
Model	HP A5120-24G EI Switch (JG234A)
VLANs	4094