Administrator Guide

Port-Based Traffic Control 851
bandwidth on the port. If the ingress rate of that type of packet is greater than
the configured threshold level the port drops the excess traffic until the
ingress rate for the packet type falls below the threshold.
When configuring the limit in terms of link bandwidth, the actual rate of
ingress traffic required to activate storm-control is based on the size of
incoming packets, and a hard-coded average packet size of 512 bytes is used
to calculate a packet-per-second (pps) rate, as the forwarding-plane requires
PPS versus an absolute rate in Kbps. For example, if the configured limit is
10% on a 1 Gbps link, this is converted to ~25000 PPS, and this PPS limit is
set in the hardware.
What are Protected Ports?
The switch supports up to three separate groups of protected ports. Traffic
can flow between protected ports belonging to different groups, but not
within the same group.
A port can belong to only one protected port group. You must remove an
interface from one group before adding it to another group.
Port protection occurs within a single switch. Protected port configuration
does not affect traffic between ports on two different switches. No traffic
forwarding is possible between two protected ports.
What is Error Recovery?
The error recovery feature enables the administrator to configure the switch
to automatically bring interfaces that have been diagnostically disabled back
into service automatically. The administrator may configure the causes for
which error recovery will bring an interface back into service and may also
configure the time interval over which error recovery is attempted. If an
interface brought back into service by the error recovery mechanism has a
subsequent failure, it will again be diagnostically disabled.
What is Link Local Protocol Filtering?
The Link Local Protocol Filtering (LLPF) feature can help troubleshoot
network problems that occur when a network includes proprietary protocols
running on standards-based switches. LLPF allows Dell Networking N1500,
N2000, N3000, and N4000 Series switches to filter out various Cisco
proprietary protocol data units (PDUs) and/or ISDP packets if problems