Packet Flow Issues
Packets could be dropped for the following reasons:
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Software-switched packets could be dropped because of Control Plane Policing (CoPP).
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Hardware-switched packets could be dropped by the hardware because of a bandwidth limitation.
Beginning with Cisco NX-OS Release 10.3.(1)F, the following CLIs are supported on Cisco Nexus 9300 and 9500 Cloud Scale switches.
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show hardware internal statistics module-all all : Displays the statistics of active modules.
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show hardware internal statistics module <module-no> all : Displays the statistics of a particular active module from supervisor.
Packets Dropped Because of Rate Limits
Use the show hardware rate-limit command to determine if packets are being dropped because of a rate limit.
switch(config)# show hardware rate-limit module 1
Units for Config: packets per second
Allowed, Dropped & Total: aggregated since last clear counters
Rate Limiter Class Parameters
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access-list-log Config : 100
Allowed : 0
Dropped : 0
Total : 0
Packets Dropped Because of CoPP
Use the show policy-map interface control-plane command to determine if packets are being dropped because of CoPP.
switch# show policy-map interface control-plane
class-map copp-system-p-class-exception (match-any)
match exception ip option
match exception ip icmp unreachable
match exception ttl-failure
match exception ipv6 option
match exception ipv6 icmp unreachable
match exception mtu-failure
set cos 1
police cir 200 pps , bc 32 packets
module 27 :
transmitted 0 packets;
dropped 0 packets;
module 28 :
transmitted 0 packets;
dropped 0 packets;
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