Broadcast storms, Igure, Setting up back pressure and flow control on ports – GarrettCom Magnum MNS-6K User Manual
Page 100
M A G N U M 6 K S W I T C H E S , M N S - 6 K U S E R G U I D E
Port Flow Control
: Disable
Port Back Pressure
: Disable
Magnum6K25(device)##
setport port=11 flow=enable bp=enable
Magnum6K25(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
-------------------------------------------------------------------------------------------------------------
9 B1
E H 10Tx UP 10
No
E 1
-
-
10 B2
E
H 10Tx DOWN 10 No
E 1
-
-
11 JohnDoe E H 10Tx DOWN 10 No
E 1
-
-
12 JaneDoe E H 10Tx DOWN 10
No
E 1
-
-
13 B5
E F
100Tx UP 100 No
E 1
-
-
14 B6
E H 10Tx DOWN 10
No
E 1
-
-
15 B7
E H 10Tx DOWN 10
No
E 1
-
-
16 B8
E H 10Tx DOWN 10 No
E 1
-
-
Magnum6K25(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
Magnum6K25(device)##
exit
Note – the flow control and back pressure is
shown as enabled for the specific port. The
global “show port” command does not show
this detail. The back pressure and flow control
parameters are global – i.e. the same for all
the ports.
Magnum6K25#
F
IGURE
65
– Setting up back pressure and flow control on ports
Broadcast Storms
One of the best features of the Magnum 6K family of switches 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 or the network software is not properly functioning or
badly designed programs (including some network games) are used. Storms can reduce
network performance and cause bridges, routers, workstations, servers and PC's to slow down
or even crash.
j
99