Hi Leo and Campbell,I've

Tauer Drumond · ‎05-06-2014

Hi all,

Recently, I'd connected a 2960 together with a 3750-X

2960 - Port G0/1 (WS-C2960-24TT-L - SW: Version 15.0(2)SE2)

3750-X Port G1/0/9 (WS-C3750X-48 - SW: Version 15.0(2)SE2)

CRC and Input Error increase equally, only on 3750-X:

21895 input errors, 21895 CRC, 0 frame, 0 overrun, 0 ignored

They are the same.

I've tried everything to figure out what's happening. Change the cable, change duplex e speed, etc. And nothing happens

Please,

anyone has an idea to help me out?

Thank you all

acampbell · ‎05-06-2014

Hi,

Can you post

sh run int g1/0/9 - from the 3750

sh run int g0/1 from the 2960

also sh int g1/0/9

and sh int g0/1

Regards

Alex

Regards, Alex. Please rate useful posts.

Tauer Drumond · ‎05-06-2014

Hey Campbell, thanks for reply.

Follow the output below:

Switch 3750-X

-----
interface GigabitEthernet1/0/9
switchport trunk encapsulation dot1q
switchport mode trunk
switchport nonegotiate
load-interval 30
duplex full
udld port aggressive
ip dhcp snooping trust

-------

GigabitEthernet1/0/9 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is a493.4c05.ef09 (bia a493.4c05.ef09)
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)
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 00:00:04, output 00:00:00, output hang never
Last clearing of "show interface" counters 22:36:46
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 29000 bits/sec, 17 packets/sec
30 second output rate 65000 bits/sec, 61 packets/sec
     2676932 packets input, 881408261 bytes, 0 no buffer
     Received 40328 broadcasts (21174 multicasts)
     0 runts, 0 giants, 0 throttles
     38910 input errors, 38910 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 21174 multicast, 0 pause input
     0 input packets with dribble condition detected
     6945710 packets output, 3289042111 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

-------

Switch 2960

-------

interface GigabitEthernet0/1
switchport mode trunk
switchport nonegotiate
load-interval 30
------

GigabitEthernet0/1 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is 9c4e.2050.a119 (bia 9c4e.2050.a119)
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)
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 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters 22:48:59
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 49000 bits/sec, 50 packets/sec
30 second output rate 14000 bits/sec, 9 packets/sec
     6995428 packets input, 3295389496 bytes, 0 no buffer
     Received 3792687 broadcasts (3519113 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 3519113 multicast, 0 pause input
     0 input packets with dribble condition detected
     2721515 packets output, 882553595 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

Leo Laohoo · ‎05-06-2014

1. This is a copper link so I'd recommend you disable UDLD port aggressive.

2. Enable auto duplex and auto speed. The CRC and Input Errors are caused by the "duplex full" setting.

acampbell · ‎05-07-2014

Hi,

Totally agree with Leo.

Both ends of the link should be configured exactly the same as far as the physical settings are concerned.

In your set up you have full duplex ath e 3750 and auto duplex on the 2960.

For the UDLD have a read at this link:-

http://www.cisco.com/c/en/us/support/docs/lan-switching/spanning-tree-protocol/10591-77.html

Regards

Alex

Regards, Alex. Please rate useful posts.

Tauer Drumond · ‎05-07-2014

Hi Leo and Campbell,

I've tried this alrady, and nothing happens. CRC and input error increase at same time with same values

Here's the output of actuall configurations:

3750-X

GigabitEthernet1/0/9 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is a493.4c05.ef09 (bia a493.4c05.ef09)
MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
     reliability 253/255, 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 00:00:01, output 00:00:00, output hang never
Last clearing of "show interface" counters 00:00:43
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 171000 bits/sec, 140 packets/sec
30 second output rate 2428000 bits/sec, 280 packets/sec
     6216 packets input, 812642 bytes, 0 no buffer
     Received 34 broadcasts (29 multicasts)
     0 runts, 0 giants, 0 throttles
     84 input errors, 84 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 29 multicast, 0 pause input
     0 input packets with dribble condition detected
     12241 packets output, 13900470 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

interface GigabitEthernet1/0/9
switchport trunk encapsulation dot1q
switchport mode trunk
switchport nonegotiate
load-interval 30
ip dhcp snooping trust
end

-------

2960

Hardware is Gigabit Ethernet, address is 9c4e.2050.a119 (bia 9c4e.2050.a119)
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)
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 00:00:00, output 00:00:03, output hang never
Last clearing of "show interface" counters 00:04:18
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 2178000 bits/sec, 254 packets/sec
30 second output rate 158000 bits/sec, 130 packets/sec
     60331 packets input, 56292783 bytes, 0 no buffer
     Received 14890 broadcasts (12708 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 12708 multicast, 0 pause input
     0 input packets with dribble condition detected
     30715 packets output, 6022703 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

!
interface GigabitEthernet0/1
switchport mode trunk
switchport nonegotiate
load-interval 30

Leo Laohoo · ‎05-07-2014

3750-X

GigabitEthernet1/0/9 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is a493.4c05.ef09 (bia a493.4c05.ef09)
  MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
     reliability 253/255, txload 1/255, rxload 1/255

Gotcha!

You've got a cable problem.

You've got a 3750X and this is good. Run a TDR to determine WHERE the problem is.

Tauer Drumond · ‎05-07-2014

Hey Leo...
I ran a TDR test, but it seems to be all ok.. :(

show cable-diagnostics tdr interface gigabitEthernet 1/0/9
TDR test last run on: May 07 21:34:17

Interface Speed Local pair      Pair length    Remote pair Pair status
--------- ----- ---------- ------------------ ----------- --------------------
Gi1/0/9   1000M Pair A     0    +/- 10 meters Pair A        Normal
                  Pair B     0    +/- 10 meters Pair B    Normal
                Pair C     0    +/- 10 meters Pair C    Normal
                  Pair D     0    +/- 10 meters Pair D        Normal

And... issuing the commando on 2960, I got this:

TDR test last run on: May 07 21:42:34

Interface Speed Local pair Pair length        Remote pair Pair status
--------- ----- ---------- ------------------ ----------- ------------------
Gi0/1     1000M Pair A     8    +/- 10 meters Pair B      Normal
              Pair B     8    +/- 10 meters Pair A      Normal
                  Pair C     8    +/- 10 meters Pair D      Normal
                  Pair D     8    +/- 10 meters Pair C      Normal

Leo Laohoo · ‎05-07-2014

Ok. I trust TDR but I trust your "sh interface" output more.

What you've seen is not abnormal. This is true, for example, if the entire cable run has some vibrations which can cause the cable to move. That's why when you first put the "sh interface" output there was nothing suspicious. Same with your TDR. But when you published the second "sh interface" the fault materialize.

I'd start changing the cables at both ends. But I would start at the 3750-end. The 3750X TDR result doesn't smell "right".

Tauer Drumond · ‎05-08-2014

Hi Leo,

the swtiches are connected directly. No horizontal cables or patch pannel.

I've changed this cable already to a Cat6 one, but no luck.

I have eight 2960S-48FPS-L connected in this 3750-X in the same fashion, through a GLC-T and I have no problem at all. All counters are clear.

The only problem is with this different 2960-24TT-L.

I'm guessing the problem is with the 2960-24TT-L :(

acampbell · ‎05-08-2014

Hi,

As a test can you drop the connection to 100M Full duplex at both ends

Clear counters and repost outputs

Regards

Alex

Regards, Alex. Please rate useful posts.

Tauer Drumond · ‎05-13-2014

Hi Leo and Campbell,

I've changed the speed and duplex to 100 Full on both sides, but the interface in 2960 never goes UP being in duplex full (I dont know why) It only works in duplex auto.

If this interface is in "duplex auto" and 3750-x is in duplex full, the duplex on 2960 negotiates in half.
So.. I can only work in 100 Full not forced... but, CRC and input error increase at same fashion

I'll try to chaged the cable again and repeat all tests

Leo Laohoo · ‎05-08-2014

the swtiches are connected directly.

Really???? I find that hard to believe. Look at the wire maps. They are totally different.

I've never seen one like this before. Must be MDI/MDI-X kicking in.

I've changed this cable already to a Cat6 one, but no luck.

Forgive me but I ain't belittling you. Can I ask you to change the cable TWO MORE TIMES?

There's a reason why I always carry three items of the same part.

3750-x Same CRC and Input Error