Hi,
I have detected a strange problem on our C2950 switch: The 'no-buffer' and 'ignored' counter keeps increasing with 1.5 packets/sec on its trunk link to a different switch. As far as I can tell the trunk is experiencing low traffic, port settings are OK and the switch is on its latest firmware version, however, these counters keep increasing. There's no information in the switchs' logs either.
At the moment there is no impact but users who connect to that switch complain about random slowness, so I am trying to eliminate all possible causes.
Any idea what is causing this or what further steps I could take to find the cause of this issue?
Here's the switch's output:
alrswcc15#sh ver
Cisco Internetwork Operating System Software
IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(22)EA14, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2010 by cisco Systems, Inc.
Compiled Tue 26-Oct-10 10:35 by nburra
Image text-base: 0x80010000, data-base: 0x80570000
ROM: Bootstrap program is C2950 boot loader
alrswcc15 uptime is 2 days, 1 hour, 57 minutes
System returned to ROM by power-on
System restarted at 09:40:18 CET Tue Aug 4 2015
System image file is "flash:/c2950-i6q4l2-mz.121-22.EA14.bin"
cisco WS-C2950C-24 (RC32300) processor (revision B0) with 20956K bytes of memory.
Processor board ID FAB0524Q2VB
Last reset from system-reset
Running Enhanced Image
26 FastEthernet/IEEE 802.3 interface(s)
32K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address: 00:06:28:FF:7E:00
Motherboard assembly number: 73-5750-08
Motherboard serial number: FAB0524A0SW
Model revision number: B0
Model number: WS-C2950C-24
System serial number: FAB0524Q2VB
Configuration register is 0xF
alrswcc15#sh run int fa0/24
Building configuration...
Current configuration : 109 bytes
!
interface FastEthernet0/24
description Link alrswcc11
switchport mode trunk
switchport nonegotiate
end
alrswcc15#sh int fa0/24
FastEthernet0/24 is up, line protocol is up (connected)
Hardware is Fast Ethernet, address is 0006.28ff.7e18 (bia 0006.28ff.7e18)
Description: Link alrswcc11
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, media type is 100BaseTX
input flow-control is unsupported output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:07, output hang never
Last clearing of "show interface" counters never
Input queue: 1/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 25000 bits/sec, 31 packets/sec
5 minute output rate 14000 bits/sec, 9 packets/sec
6053768 packets input, 823851500 bytes, 102778 no buffer
Received 3980576 broadcasts (2093982 multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 102778 ignored
0 watchdog, 2093981 multicast, 0 pause input
0 input packets with dribble condition detected
1850712 packets output, 608056922 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
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
alrswcc15#sh buffer
Buffer elements:
498 in free list (500 max allowed)
5002681 hits, 0 misses, 0 created
Public buffer pools:
Small buffers, 104 bytes (total 28, permanent 25, peak 109 @ 2d01h):
28 in free list (20 min, 60 max allowed)
4027909 hits, 59 misses, 132 trims, 135 created
0 failures (0 no memory)
Middle buffers, 600 bytes (total 18, permanent 15, peak 39 @ 2d01h):
16 in free list (10 min, 30 max allowed)
62742 hits, 19 misses, 24 trims, 27 created
0 failures (0 no memory)
Big buffers, 1524 bytes (total 6, permanent 5, peak 7 @ 2d01h):
6 in free list (5 min, 10 max allowed)
55451 hits, 1 misses, 25 trims, 26 created
0 failures (0 no memory)
VeryBig buffers, 4520 bytes (total 2, permanent 0, peak 2 @ 2d01h):
2 in free list (0 min, 10 max allowed)
3455 hits, 1 misses, 0 trims, 2 created
0 failures (0 no memory)
Large buffers, 5024 bytes (total 0, permanent 0):
0 in free list (0 min, 5 max allowed)
0 hits, 0 misses, 0 trims, 0 created
0 failures (0 no memory)
Huge buffers, 18024 bytes (total 0, permanent 0):
0 in free list (0 min, 2 max allowed)
0 hits, 0 misses, 0 trims, 0 created
0 failures (0 no memory)
Interface buffer pools:
Calhoun Packet Receive Pool buffers, 1560 bytes (total 256, permanent 256):
222 in free list (0 min, 256 max allowed)
2975045 hits, 0 misses
And here is the output from the other side of the trunk:
alrswcc11#sh run int fa0/48
Building configuration...
Current configuration : 104 bytes
!
interface FastEthernet0/48
description ALRSWCC15
switchport mode trunk
switchport nonegotiate
end
alrswcc11#sh int fa0/48
FastEthernet0/48 is up, line protocol is up (connected)
Hardware is Fast Ethernet, address is 2401.c78b.7db0 (bia 2401.c78b.7db0)
Description: ALRSWCC15
MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, media type is 10/100BaseTX
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:16, output 00:00:00, output hang never
Last clearing of "show interface" counters 1w6d
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 70370
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 15000 bits/sec, 10 packets/sec
5 minute output rate 68000 bits/sec, 50 packets/sec
20566880 packets input, 4120862842 bytes, 0 no buffer
Received 277053 broadcasts (217356 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 217356 multicast, 0 pause input
0 input packets with dribble condition detected
49652483 packets output, 6666620397 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 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
Any help will be greatly appreciated!
