5-9
Cisco 7401ASR Installation and Configuration Guide
OL-5419-01 B0
Chapter5 Troubleshooting PXF Troubleshooting Information
Packets ignored: 0 | ring space:
shadow ring full: 0 | shadow ring: 16384
in ring full: 0 | inring: 968
PXF inactive: 0
tx credits: 16230330 | delayed credits: 0
holdq enqueues: 0 | requeue drops: 0
interrupts: 40538 | interrupt misses: 1947
interrupt packets: 53326
pending read bytes: 0
Interface Pkts In Chars In Pkts Out Chars Out Punted Dropped
Fa0/0 0 0 30000000 1740000000 970 0
Et1/0 0 0 0 0 21309 0
Et1/1 0 0 0 0 0 0
Et1/2 0 0 0 0 0 0
Et1/3 0 0 0 0 0 0
Se2/0 0 0 0 0 963 0
Se2/1 0 0 0 0 0 0
Se2/2 0 0 0 0 0 0
Se2/3 0 0 0 0 0 0
Fa3/0 0 0 0 0 963 0
PO4/0 30000000 1440000000 0 0 963 0
AT5/0 0 0 0 0 23192 0
Vi1 0 0 0 0 0 0
Vt1 0 0 0 0 0 0
Vi2 0 0 0 0 0 0
Vt2 0 0 0 0 0 0
Note CPU usage becomes more efficient as packet load increases. For e xample, if y ou are running at 6 0% CPU
with only 33% of customer load on the system, this does not mean tha t yo u nee d 180% C PU fo r 1 00%
of customers. Part of the original 60% CPU usage is overhead usage, which does not increase as packet
load increases.
Ignored Packets
Packet ignores on an interface may result from high CPU usag e. Enter the show interfaces command to
display any input ignores:
Router# show interfaces ethernet 0/0
Ethernet0/0 is up, line protocol is up
...
21 input errors, 0 CRC, 0 frame, 0 overrun, 21 ignored
Packets are ignored if there is no available CPU to accept the new packet. This can happen if the router
is overloaded with traffic, but can also happen if the interface is faulty. If ignores are present on all
interfaces, then the router is probably overloaded with traffic, or does not have sufficient free buffers in
the pool that match the maximum transmission unit (MTU) on interfaces. In the latter case , an increm ent
of the ignored counter is followed by an increment of the n o buffer co unte r:
Router# show interfaces serial 0/0
...
1567 packets input, 0 bytes, 22 no buffer
22 input errors, 0 CRC, 0 frame, 0 overrun, 22 ignored, 0 abort