Undersize error between 3560 and CSS 11500

Rojer-bkk · ‎02-10-2011

Hi,

I found increment of undersize frames error on 3560 interface attached to CSS 11500. I try to search bug and release notes but switch use new software 12.2(25)SEB1 which issue was fixed. 3560 trunk to CSS 11500. How can i troubleshoot about this? Thanks

Transmit GigabitEthernet0/49             Receive
   3414178857 Bytes                       2916815079 Bytes
    913070379 Unicast frames               423322763 Unicast frames
      1347482 Multicast frames                 19728 Multicast frames
      1942287 Broadcast frames                     0 Broadcast frames
            0 Too old frames               962227303 Unicast bytes
            0 Deferred frames                4950996 Multicast bytes
            0 MTU exceeded frames                  0 Broadcast bytes
            0 1 collision frames                   0 Alignment errors
            0 2 collision frames                   0 FCS errors
            0 3 collision frames                   0 Oversize frames
            0 4 collision frames             4004169 Undersize frames
            0 5 collision frames                   0 Collision fragments
            0 6 collision frames
            0 7 collision frames           207403453 Minimum size frames
            0 8 collision frames            27121573 65 to 127 byte frames
            0 9 collision frames             9375088 128 to 255 byte frames
            0 10 collision frames           17373017 256 to 511 byte frames
            0 11 collision frames          118483078 512 to 1023 byte frames
            0 12 collision frames           43586282 1024 to 1518 byte frames
            0 13 collision frames                  0 Overrun frames
            0 14 collision frames                  0 Pause frames
            0 15 collision frames
            0 Excessive collisions                 0 Symbol error frames
            0 Late collisions                      0 Invalid frames, too large
            0 VLAN discard frames                  0 Valid frames, too large
            0 Excess defer frames                  0 Invalid frames, too small
     71965485 64 byte frames                 4004169 Valid frames, too small
     44625512 127 byte frames
     17220361 255 byte frames                      0 Too old frames
     45382505 511 byte frames                      0 Valid oversize frames
    712768170 1023 byte frames                     0 System FCS error frames
     24398115 1518 byte frames                     0 RxPortFifoFull drop frame
            0 Too large frames
            0 Good (1 coll) frames
            0 Good (>1 coll) frames

sdheer · ‎02-10-2011

Hi Rojer,

Check the speed and duplex setting on the port connected to CSS 11500 .If the speed and duplex is hard coded ,change it to auto and then see if undersize errors are still incrementing.

Regards,

Swati

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Rojer-bkk · ‎02-10-2011

Hi Swati,

Thanks for your feedback.

Those ports was setup to be 'Auto' mode.

!
interface GigabitEthernet0/49
description csthbaing-01 1/1
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface GigabitEthernet0/50
description csthbaing-01 1/2
switchport trunk encapsulation dot1q
switchport mode trunk

!

CSS configuration

interface 1/1
trunk

vlan 281

vlan 282

vlan 283

vlan 284

interface 1/2
trunk

vlan 281

vlan 282

vlan 283

vlan 284

sdheer · ‎02-10-2011

Hi Rojer,

Undersized Frames: When using dot1q on the trunk interface on the Catalyst 3750, runts may be seen on show interfaces output because valid dot1q encapsulated packets which are 61 to 64 bytes including the q-tag are counted by the Catalyst 3750 as undersized frames, even though these packets are forwarded correctly.

Regarding the undersize errors on ports connected to CSS 1150, there are some
bugs which match your issue.

I believe that you are hit by bug ID ::

CSCec14238

CSCec53648

This problem affects the Catalyst 2970, 3560, and 3750 family of switches.

Here are the details:

3750 connected using dot1q cause Runts increase on interface.

Symptom:
When using dot1q on trunk interface on the Cat3750, runts may be seen on
show interface output because valid dot1q encapsulated packets which are
61-64 bytes including the q-tag are counted by the Cat3750 as undersized
frames, even though these packets are forwarded correctly. In addition,
these packets are not reported in the appropriate category (unicast,
multicast, broadcast) in receive statistics.

Workaround:
There is no workaround.

Please see additional details of the bug fix and further limitations in the
fixed IOS release:

Whenever valid 64-66 bytes dot1q packets are sent to a dot1q port,
an orange led will be blinking even though the packet is successfully sent.
After this fix, the led will still be amber blinking but a show interface
will not report any runts or error packets. Show controller
ethernet-controller
reports Undersize frames.

The root cause of the problem is that the port ASIC counts valid 61-64
byte .1q encapsulated packets as undersized frames even though these packets
are padded with zeros and forwarded correctly.

This is only a cosmetic and this kind of errors won't affect the operation
of your switch or network. This is ASIC limitation.

Can you paste " show interface x/y " output here.

Regards,

Swati

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Rojer-bkk · ‎02-10-2011

Hi Swati,

I research and found this bug as well, anyway, 3560 used image 12.2(25)SEB1 which bug should be fixed. Thanks

GigabitEthernet0/49 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is 0014.6975.2031 (bia 0014.6975.2031)
Description: csthbaing-01 1/1
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 3/255, rxload 3/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 1000Mb/s, link type is auto, media type is 1000BaseSX SFP
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters 1d05h
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 13252000 bits/sec, 3676 packets/sec
5 minute output rate 14259000 bits/sec, 4180 packets/sec
     190011582 packets input, 2372691905 bytes, 0 no buffer
     Received 6972 broadcasts (0 multicast)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 6972 multicast, 0 pause input
     0 input packets with dribble condition detected
     271103070 packets output, 2159618815 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 PAUSE output
     0 output buffer failures, 0 output buffers swapped out

GigabitEthernet0/50 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is 0014.6975.2032 (bia 0014.6975.2032)
Description: csthbaing-01 1/2
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 1000Mb/s, link type is auto, media type is 1000BaseSX SFP
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters 1d05h
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 10000 bits/sec, 9 packets/sec
5 minute output rate 1000 bits/sec, 2 packets/sec
     905122 packets input, 124772810 bytes, 0 no buffer
     Received 905115 broadcasts (0 multicast)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 215580 multicast, 0 pause input
     0 input packets with dribble condition detected
     267737 packets output, 20225256 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 PAUSE output
     0 output buffer failures, 0 output buffers swapped out

sdheer · ‎02-10-2011

Hi Rojer,

I reseacrhed a little and found this bug:

CSCsh17651

Symptom:


When using dot1q on trunk interface on the Cat3560, undersize packets may be seen on 
show interface output because valid dot1q encapsulated packets which are 
61-64 bytes including the q-tag are counted by the Cat3560 as undersized 
frames, even though these packets are forwarded correctly. In addition,
these packets are not reported in the appropriate category (unicast, 
multicast, broadcast) in receive statistics. 

Workaround:
There is no workaround.

The above  is fixed in 12.2(37)SE code and higher.

Regards,
Swati

Rojer-bkk · ‎02-14-2011

I will try to upgrade to 122-53.SE2 code and monitor once again. Thanks