2960S Too large frames

[robert]

Hi,

I have 2 2960S configured as a flexstack with a etherchannel containing 4 ports connected to a Windows storage server, where I have configured 4 broadcom nics as a etherchannel. On the Broadcom nic team, I have enabled a mtu of 9000 bytes.

It is working fine, no user complaints, but looking at the 2960 interfaces statistics to the etherchannel, I see <too large frames> and <valid frames, too large> on all 4 interfaces.

1 52    WS-C2960S-48TS-L   15.0(2)SE4            C2960S-UNIVERSALK9-M
2 52    WS-C2960S-48TS-L   15.0(2)SE4            C2960S-UNIVERSALK9-M

System MTU size is 1500 bytes
System Jumbo MTU size is 9198 bytes
System Alternate MTU size is 1500 bytes
Routing MTU size is 1500 bytes

Etherchannel1:
Group  Port-channel  Protocol    Ports
------+-------------+-----------+-----------------------------------------------
1      Po1(SU)         LACP      Gi1/0/13(P) Gi1/0/14(P) Gi2/0/13(P)
                                 Gi2/0/14(P)

interface GigabitEthernet1/0/13
 description PortrChannel to Dell Storage server
 switchport access vlan 2
 switchport mode access
 spanning-tree portfast
 channel-group 1 mode active
!
interface GigabitEthernet1/0/14
 description PortrChannel to Dell Storage server
 switchport access vlan 2
 switchport mode access
 spanning-tree portfast
 channel-group 1 mode active

interface GigabitEthernet2/0/13
 description Portchannel to DELL Storage server
 switchport access vlan 2
 switchport mode access
 spanning-tree portfast
 channel-group 1 mode active
!
interface GigabitEthernet2/0/14
 description Portchannel to DELL Storage server
 switchport access vlan 2
 switchport mode access
 spanning-tree portfast
 channel-group 1 mode active

sh controllers ethernet-controller gig1/0/13
Transmit: 377631134 Too large frames
Receive: 129713868 Valid frames, too large

sh controllers ethernet-controller gig1/0/14
Transmit: 747469882 Too large frames
Receive: 127341965 Valid frames, too large

sh controllers ethernet-controller gig2/0/13
Transmit: 191980042 Too large frames
Receive: 112521159 Valid frames, too large

sh controllers ethernet-controller gig2/0/14
Transmit: 83379551 Too large frames
Receive:  139446079 Valid frames, too large

Why am I seeing too large frames on those ports when I have enabled jumbo frames on the switch and server?

Regards
Robert
 

[Leo Laohoo]

Those are fine.  What you need to be worried about are "total output drops".  

[robert]

Thanks.

As far as I see only gig1/0/14 has a pretty big output drops - 186030.
But if the number is since last reboot, then I guess the number is okay?

2960S-Core-stack uptime is 1 year, 18 weeks, 4 days, 1 hour, 34 minutes

2960S-Core-stack#sh int gig1/0/13
GigabitEthernet1/0/13 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is f41f.c2a0.9b0d (bia f41f.c2a0.9b0d)
  Description: PortrChannel to Dell Storage server
  MTU 9198 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)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:30, output 00:00:05, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 1284
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     2795613655 packets input, 3161835024205 bytes, 0 no buffer
     Received 11288132 broadcasts (2752765 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 2752765 multicast, 29914 pause input
     0 input packets with dribble condition detected
     2189137478 packets output, 4058438953424 bytes, 0 underruns
     0 output errors, 0 collisions, 1 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
2960S-Core-stack#sh int gig1/0/14
GigabitEthernet1/0/14 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is f41f.c2a0.9b0e (bia f41f.c2a0.9b0e)
  Description: PortrChannel to Dell Storage server
  MTU 9198 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)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:12, output 00:00:02, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 186030
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 1000 bits/sec, 1 packets/sec
     3707724536 packets input, 4643627468072 bytes, 0 no buffer
     Received 6787158 broadcasts (2657211 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 2657211 multicast, 128960 pause input
     0 input packets with dribble condition detected

2960S-Core-stack#sh int gig2/0/13
GigabitEthernet2/0/13 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is 7010.5c69.d58d (bia 7010.5c69.d58d)
  Description: Portchannel to DELL Storage server
  MTU 9198 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)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, output 00:00:58, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 4
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 166000 bits/sec, 18 packets/sec
     3539049724 packets input, 3829512132321 bytes, 0 no buffer
     Received 7243953 broadcasts (2913343 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 2913343 multicast, 3251 pause input
     0 input packets with dribble condition detected

2960S-Core-stack#sh int gig2/0/14
GigabitEthernet2/0/14 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is 7010.5c69.d58e (bia 7010.5c69.d58e)
  Description: Portchannel to DELL Storage server
  MTU 9198 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)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, output 00:00:07, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 11046
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     3520338138 packets input, 4126381780859 bytes, 0 no buffer
     Received 7053502 broadcasts (2794515 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 2794515 multicast, 6051 pause input
     0 input packets with dribble condition detected
     2656057046 packets output, 1761174558434 bytes, 0 underruns
     0 output errors, 0 collisions, 1 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

[Leo Laohoo · Accepted solution]

IF the uptime of the switch is that long AND the interface counters have NOT been cleared then the numbers you are seeing is fine.  

Make sure your input errors and CRC remain "0".