3845 CEF enabled with throughput at process switched level

[rugman66]

Hello,

I have a 3845 router as the GW running an NM-16ESW card with one GigE port being used as the trunk to the backbone c2960x switch. CEF is enabled globally on the 3845 and on the NM-16ESW GigE port. However the NM-16ESW GigE port input queue is dropping a very high amount of packets, and the throughput speed is an average of 9Mb/s. It should be in the 200Mb/s range when running CEF for the 3845 platform according to this Cisco doc. 

https://community.cisco.com/t5/routing/process-switching-in-routers/td-p/1122323?attachment-id=83559

Would very much appreciate any SME suggestions on where to troubleshoot. I'll run and post any show command requested.

[Georg Pauwen]

Hello,

post the output of 'show interfaces x' of both connected GigabitEthernet ports...

[rugman66]

Sure, 

I swapped the 2960 back for the c4948 just fyi.

Thanks

3845

englrn-hackshare-gw1-rack-10#sh interfaces gigabitEthernet 1/0
GigabitEthernet1/0 is up, line protocol is up
Hardware is Gigabit Ethernet, address is c471.fe4a.9b4b (bia c471.fe4a.9b4b)
Description: Trunk to 4948_left
MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
output flow-control is off, input flow-control is off
0 pause input, 0 pause output
Full-duplex, 1000Mb/s
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:31, output never, output hang never
Last clearing of "show interface" counters 1d01h
Input queue: 0/100/1876447/0 (size/max/drops/flushes); Total output drops: 556
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 299000 bits/sec, 96 packets/sec
5 minute output rate 364000 bits/sec, 89 packets/sec
45626513 packets input, 3052682201 bytes, 0 no buffer
Received 48623 broadcasts (0 multicasts)
0 runts, 0 giants, 0 throttles
4071 input errors, 1 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
0 input packets with dribble condition detected
65195741 packets output, 725041682 bytes, 0 underruns
1 output errors, 0 collisions, 0 interface resets
2767 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 pause output
0 output buffer failures, 0 output buffers swapped out

c4948

englrn-rack-10-4948-backbone#sh interfaces gigabitEthernet 1/48
GigabitEthernet1/48 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet Port, address is 001d.a26e.c42f (bia 001d.a26e.c42f)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 1000Mb/s, link type is auto, media type is 10/100/1000-TX
Media-type configured as RJ45 connector
input flow-control is off, output flow-control is off
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 511000 bits/sec, 126 packets/sec
5 minute output rate 776000 bits/sec, 153 packets/sec
15926388707 packets input, 18471338162060 bytes, 0 no buffer
Received 58337552 broadcasts (49941775 multicast)
0 runts, 0 giants, 0 throttles
1 input errors, 1 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
12175631128 packets output, 5931305547568 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out

[rugman66]

Central CEF is enabled

englrn-hackshare-gw1-rack-10#sh cef state
CEF Status:
RP instance
common CEF enabled
IPv4 CEF Status:
CEF enabled/running
dCEF disabled/not running
CEF switching enabled/running
universal per-destination load sharing algorithm, id 7AD4FEAD

CEF shows enabled on the interface with this show command

englrn-hackshare-gw1-rack-10#sh ip cef gigabitEthernet 1/0 detail
IPv4 CEF is enabled and running
VRF Default
169 prefixes (169/0 fwd/non-fwd)
Table id 0x0
Database epoch: 0 (169 entries at this epoch)

CEF Does not show in the “show interfaces gigabitEthernet 1/0” command

englrn-hackshare-gw1-rack-10#sh interfaces gigabitEthernet 1/0

GigabitEthernet1/0 is up, line protocol is up

  Hardware is Gigabit Ethernet, address is c471.fe4a.9b4b (bia c471.fe4a.9b4b)

  Description: Trunk to 4948_left

  MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,

     reliability 255/255, txload 1/255, rxload 1/255

  Encapsulation ARPA, loopback not set

  Keepalive set (10 sec)

  output flow-control is off, input flow-control is off

  0 pause input, 0 pause output

  Full-duplex, 1000Mb/s

  ARP type: ARPA, ARP Timeout 04:00:00

  Last input 00:00:40, output never, output hang never

  Last clearing of "show interface" counters 2d00h

  Input queue: 0/100/3718489/0 (size/max/drops/flushes); Total output drops: 966

  Queueing strategy: fifo

  Output queue: 0/40 (size/max)

  5 minute input rate 265000 bits/sec, 109 packets/sec

  5 minute output rate 568000 bits/sec, 115 packets/sec

     85716641 packets input, 3375351072 bytes, 0 no buffer

     Received 79867 broadcasts (0 multicasts)

     0 runts, 0 giants, 0 throttles

     4071 input errors, 1 CRC, 0 frame, 0 overrun, 0 ignored

     0 watchdog, 0 multicast, 0 pause input

     0 input packets with dribble condition detected

     124138662 packets output, 3665235943 bytes, 0 underruns

     1 output errors, 0 collisions, 0 interface resets

     2767 unknown protocol drops

     0 babbles, 0 late collision, 0 deferred

     0 lost carrier, 0 no carrier, 0 pause output

     0 output buffer failures, 0 output buffers swapped out

Also the gigabitEthernet 1/0 interface is not listed when running the

“show ip cef” command and is exclusively process switching. Note the

output below

englrn-hackshare-gw1-rack-10#sh interfaces gigabitEthernet 1/0 stats

GigabitEthernet1/0

          Switching path    Pkts In   Chars In   Pkts Out  Chars Out

               Processor   85740948 3379504877  124168172 3690622687

             Route cache          0          0          0          0

                   Total   85740948 3379504877  124168172 3690622687