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Chapter 30 Error Disable
XS1920 Series User’s Guide
272
30.4 CPU Protection Configuration
Switches exchange protocol control packets in a network to get the latest networking information.
If a switch receives large numbers of control packets, such as ARP, BPDU or IGMP packets, which
are to be processed by the CPU, the CPU may become overloaded and be unable to handle regular
tasks properly.
The CPU protection feature allows you to limit the rate of ARP, BPDU and IGMP packets to be
delivered to the CPU on a port. This enhances the CPU efficiency and protects against potential DoS
attacks or errors from other network(s). Then, you can choose to drop or bypass the control
packets, decrease the priority value to CPU of control packets that exceed the specified rate limit or
disable a port on which the packets are received.
Use this screen to limit the maximum number of control packets (ARP, BPDU and/or IGMP) that the
Switch can receive or transmit on a port. Click the
Click Here
link
next to
CPU protection
in the
Advanced Application > Errdisable
screen to display the screen as shown.
Note: After you configure this screen, make sure you also enable error detection for the
specific control packets in the
Advanced Application
>
Errdisable
>
Errdisable
Detect
screen.
Mode
This field shows the mode of the cause.
•
inactive-port
- The Switch disables the port on which the control packets are received.
•
inactive-reason
- The Switch drops all the specified control packets (such as BPDU) on
the port.
•
rate-limitation
- The Switch drops the additional control packets the port(s) has to
handle in every one second.
Rate
This field displays how many control packets this port can receive or transmit per second. It
can be adjusted in CPU Protection.
0
means no rate limit.
Status
This field displays the errdisable status
•
Forwarding
: The Switch is forwarding packets. Rate-limitation mode is always in
Forwarding
status.
•
Err-disable
: The Switch disables the port on which the control packets are received
(inactive-port) or drops specified control packets on the port (inactive-reason)
Recovery
Time
This field displays the time (seconds) left before the port(s) becomes active of Errdisable
Recovery.
Total
Dropped
This field displays the total packet number dropped by this port where the packet rate
exceeds the rate of mode rate-limitation.
Table 132
Advanced Application > Errdisable > Errdisable Status (continued)
LABEL
DESCRIPTION
Summary of Contents for XS1920 Series
Page 18: ...18 PART I User s Guide ...
Page 32: ...32 PART II Technical Reference ...
Page 177: ...Chapter 21 Classifier XS1920 Series User s Guide 177 Figure 122 Classifier Example EXAMPLE ...
Page 408: ...Appendix C IPv6 XS1920 Series User s Guide 408 ...
Page 412: ...Appendix D Legal Information XS1920 Series User s Guide 412 Environmental Product Declaration ...