User guide

Chapter 3: Configuring the FN100
Page 3-16 Fast Network 100 User Guide
Use the community command to assign a community name. At the LCM
prompt:
1. Type community
2. Enter the old community name.
If one has not been assigned, you do not need to enter anything. LCM
prompts you for the new community name.
3. Enter the new community name.
LCM prompts you to verify the new community name by retyping it.
4. Retype the new community name.
3.13 CONFIGURING MULTICAST STORM PROTECTION
The FN100 provides automatic protection against multicast storms.
Multicast storms are excessive broadcasts to all ports, typically caused by
a malfunctioning device. They can result in severe network performance
problems, including causing the network to crash.
To protect against multicast storms, you must define an acceptable rate for
multicast traffic across a port. Each FN100 port can be individually
configured for automatic multicast storm protection. You define what
level of multicasts the FN100 will recognize as a multicast storm by
specifying the number of multicast packets that can be transmitted within
a given time period.
For example, if you configure the FN100 to transmit onto Port 3 no more
than five multicasts per 60 seconds, any multicasts destined for Port 3 are
discarded after the first five multicasts. After 60 seconds have elapsed,
another five multicasts to Port 3 will be allowed. This maintains an
effective maximum rate of five multicast packets per minute.
NOTE
LCM does not allow you to configure for multicast storm
protection. You must use a SNMP-based NMS. See the
documentation that came with your NMS for configuration
instructions.