4 broadcast storms, Roadcast, Torms – GE MULTILINK ML1200 User Manual
Page 153
CHAPTER 9: PORT MIRRORING AND SETUP
PORT MIRRORING AND SETUP
MULTILINK ML1200 MANAGED FIELD SWITCH – INSTRUCTION MANUAL
9–7
9.3.4
Broadcast Storms
One of the best features of the MultiLink ML1200 Managed Field Switch is its ability to keep
broadcast storms from spreading throughout a network. Network storms (or broadcast
storms) are characterized by an excessive number of broadcast packets being sent over
the network. These storms can occur if network equipment is configured incorrectly.
Storms can reduce network performance and cause bridges, routers, workstations, servers
and PCs to slow down or even crash.
The MultiLink ML1200 Managed Field Switch is capable of detecting and limiting storms on
each port. A network administrator can also set the maximum rate of broadcast packets
(frames) that are permitted from a particular interface. If the maximum number is
exceeded, a storm condition is declared. Once it is determined that a storm is occurring on
an interface, any additional broadcast packets received on that interface will be dropped
until the storm is determined to be over. The storm is determined to be over when a one-
second period elapses with no broadcast packets received.
Back pressure and flow control (continued)
ML1200(device)##
show port
Keys:
E
= Enable
D
= Disable
H
= Half Duplex
F
= Full Duplex
M
= Multiple VLAN's
NA = Not Applicable
LI = Listening
LE = Learning
F
= Forwarding
B
= Blocking
Port
Name
Control
Dplx
Media
Link
Speed
Part
Auto
VlanID
GVRP
STP
-------------------------------------------------------------------------------
1
B1
E
H
10Tx
UP
10
No
E
1
-
-
2
B2
E
H
10Tx
DOWN
10
No
E
1
-
-
3
JohnDoe
E
H
10Tx
DOWN
10
No
E
1
-
-
4
JaneDoe
E
H
10Tx
DOWN
10
No
E
1
-
-
5
B5
E
F
100Tx
UP
100
No
E
1
-
-
6
B6
E
H
10Tx
DOWN
10
No
E
1
-
-
ML1200(device)##
show port=11
Configuration details of port 11
--------------------------------------------------
Port Name
: JohnDoe
Port Link State
: DOWN
Port Type
: TP Port
Port Admin State
: Enable
Port VLAN ID
: 1
Port Speed
: 10Mbps
Port Duplex Mode
: half-duplex
Port Auto-negotiation State
: Enable
Port STP State
: NO STP
Port GVRP State
: No GVRP
Port Priority Type
: None
Port Security
: Enable
Port Flow Control
: Enable
Port Back Pressure
: Enable
Port Link Loss Alert
: Enabled
Note that the flow control and back pressure is
shown as enabled for the specific port. The global
show port
command does not provide this detail.
The back pressure and flow control parameters
are global – i.e., the same for all ports.