Involved Products and Versions
S9300 V200R001
Networking
As shown in Figure 1-1, the S9300 is connected to a camera through the interface GE2/0/10.
Figure 1-1 Networking diagram for the fault that the S9300 fails to ping a camera
Fault Symptom
The S9300 fails to ping a camera.
Cause Analysis
The rate limit is enabled for ICMP packets, and ICMP packets are discarded. As a result, the S9300 fails to ping the camera.
Troubleshooting Procedure
Step 1 Run the display cpu-defend statistics allcommand to check statistics about the packets sent to the CPU. The command output shows that a large number of ICMP packets are discarded.
<S9300> display cpu-defend
statistics all
Statistics on mainboard:
-------------------------------------------------------------------------------
Packet Type Pass(Bytes)
Drop(Bytes) Pass(Packets) Drop(Packets)
-------------------------------------------------------------------------------
icmp
754529686
0 9672793 0
-------------------------------------------------------------------------------
Statistics on slot 1:
-------------------------------------------------------------------------------
Packet Type Pass(Bytes) Drop(Bytes)
Pass(Packets) Drop(Packets)
-------------------------------------------------------------------------------
icmp
40999663 18688 405269
20
-------------------------------------------------------------------------------
Statistics on slot 2:
-------------------------------------------------------------------------------
Packet Type Pass(Bytes) Drop(Bytes)
Pass(Packets) Drop(Packets)
-------------------------------------------------------------------------------
icmp
353711830k 9195452 5522622743
138905
Step 2 Run the display logbuffer command. The command output shows that the global rate of ICMP packets and the rate of ICMP packets on the interface exceed the limit.
Jun 30 2017 11:10:07+08:00 S9306
%SECE/4/ICMP_GLOBAL_RATELIMIT(l)[159]:Rate of global icmp packets exceeds
the limit( Threshold=100 packets per second).
Jun 30 2017 11:05:05+08:00 S9306 %SECE/4/ICMP_GLOBAL_RATELIMIT(l)[161]:Rate
of global icmp packets exceeds the limit( Threshold=100 packets per
second).
Jun 30 2017 10:55:02+08:00 S9306 %SECE/4/ICMP_GLOBAL_RATELIMIT(l)[165]:Rate
of global icmp packets exceeds the limit( Threshold=100 packets per
second).
Jun 30 2017 09:01:28+08:00 S9306 %SECE/4/ICMP_INTF_RATELIMIT(l)[219]:Rate
of icmp packets on interface exceeds the limit(SourceInterface=GigabitEthernet2/0/10,
Threshold=100 packets per second).
Jun 30 2017 08:56:27+08:00 S9306 %SECE/4/ICMP_INTF_RATELIMIT(l)[221]:Rate
of icmp packets on interface exceeds the limit(SourceInterface=GigabitEthernet2/0/10,
Threshold=100 packets per second).
Step 3 By default, the rate limit is enabled for ICMP packets in the S9300 V200R001 (by running the icmp rate-limit enablecommand), and the ICMP packet rate limit on interfaces and global rate limit are 100 pps.
Run the undo icmp rate-limit enablecommand to disable the global ICMP rate limit, or run the icmp-reply fastcommand to enable fast ICMP reply. Then the S9300 can ping the camera.
----End
Conclusions and Suggestions
In the S9300 V200R001 and earlier versions, the rate limit is enabled for ICMP packets. In versions later than V200R001, the rate limit is disabled for ICMP packets.
This is what I want to talk about/share with you today, thank you!