Enterasys Networks 2H252-25R User Manual

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Overview
1-4
Introduction
1.1.5
Remote Monitoring (RMON)
The 2H252-25R supports all nine Ethernet RMON groups. The Statistics, Alarms, Events and 
History groups are enabled on all ports by default. 
Enterasys Networks RMON Actions is a vendor-specific extension of RMON and provides the 
ability to set an “Action” on any SNMP MIB variable. The Action can be triggered by any RMON 
Event and/or Alarm. An example of an Action would be to turn off a MIB-2 interface if a 
broadcast threshold is crossed. 
1.1.6
Broadcast Suppression
Broadcast Suppression enables a user to set a desired limit of receive broadcast frames per port/per 
second to be forwarded out the other ports on the device. Any broadcast frames above this 
specified limit are dropped. In the event that broadcast frames are being suppressed, multicast and 
unicast frames continue to be switched.
1.1.7
Port/VLAN Redirect Functions
The port redirect function, also referred to as “Port Mirroring,” is a troubleshooting tool used to 
map traffic from a single source port to a single destination port within the device. This feature 
allows frames, including those with errors, to be copied and sent to an analyzer or RMON probe. 
The analyzer or RMON probe will see the data as if it were directly connected to the LAN segment 
of the source port.
The VLAN redirect function is similar to the port redirect function except that the frames received 
by the device are redirected to a designated destination port according to the VLAN classification 
of the frames received. Multiple VLANs can be directed to the same destination port. The VLAN 
redirect function is only supported when the device is operating as an 802.1Q switch.
1.1.8
Rate Limiting
The Rate Limiting feature enables the SmartSwitch device to have control over traffic rates on a 
per-port, per-priority basis. The network administrator can configure a rate limit (from 100 kbps to 
1 Gbps) for a given port with an associated list of IEEE 802.1p priorities (which can include one, 
some, or all of the eight priority levels defined in 802.1p). Each rate limit is specified as an 
inbound or an outbound limit. The combined rate of all traffic on the port that matches the listed 
priorities cannot exceed the programmed limit. If the rate exceeds the defined limit, frames are 
dropped until the rate falls below the limit.