CHAPTER 9: PORT MIRRORING AND SETUP
PORT SETUP
MULTILINK ML810 MANAGED EDGE SWITCH – INSTRUCTION MANUAL
9–7
9.3.4
Broadcast Storms
One of the best features of the MultiLink ML810 Managed Edge 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 ML810 Managed Edge 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)
ML810(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
- -
ML810(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
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.
