Enterasys Networks Fast Network 10 - Manual (Page 58)

Chapter 3: Configuring Your FN10
Page 3-16 Fast Network 10 User Guide
3.10 CONFIGURING MULTICAST STORM PROTECTION
The FN10 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. In many ways, this feature is similar to
filtering, however, multicast storm protection does not involve the use of
filters.
Each FN10 port can be individually configured for automatic multicast
storm protection. You define what level of multicasts the FN10 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 FN10 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.
The two Management Information Base (MIB) variables for configuring
multicast storm protection are:
• sxifTxStormCnt – specifies the maximum number of multicasts that
can be broadcast within the given time.
• sxiTxStormTime – specifies the period of time that the maximum
number of multicasts can be broadcasted.
Refer to the Fast Network 10 MIB Reference Guide for a complete listing
and description of MIB variables.
NOTE
LCM does not allow you configure for multicast storm
protection. You must use RCM or an SNMP-based NMS. See
the
RCM Reference Guide or the documentation that came
with your NMS for configuration instructions.