Network Drop Outs

[peterlyttle]

Hello, we are having a strange issue that some applications are reporting a dropped network connection, this is only for a split second that a ping would not pick up but effects things with ODBC connections etc. Can anyone advise any ways to troubleshoot the backbone which is a stacked WS-C3750G-12S (we have swapped the edge switches already to rule them out).

FYI - The edge switches have 2 fibre, 1 going to each of the 2 stacked switches.

Any help much appreciated.

Peter

 

[burtsbees]

Post a sh int of the interface that is connected to the trouble machines.

Burt

 

[jeter]

Have you placed an analyzer on your system to sniff out the issues?


SPC NVARNG
Tek-TIP Member 19,650

 

[peterlyttle]

Hi, no I havent put an analyer on the system yet, just run wireshark and span the port to another port running the software or is there something better to use?

Here is the interface of the server that is noticing the issue.

switch#sh int Gi0/20
GigabitEthernet0/20 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is xxxx.xxxx.xxxx (bia xxxx.xxxx.xxxx)
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, 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 00:00:01, output hang never
Last clearing of "show interface" counters never
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 772000 bits/sec, 659 packets/sec
5 minute output rate 1502000 bits/sec, 685 packets/sec
1964700962 packets input, 2188681563294 bytes, 0 no buffer
Received 78478 broadcasts (0 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 32 multicast, 0 pause input
0 input packets with dribble condition detected
1522451967 packets output, 388240242485 bytes, 0 underruns
0 output errors, 0 collisions, 1 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

 

[BrandonSwag]

Are there any errors on the uplink ports? Is Spanning Tree running across links or do you have layer 3 switches in the accesss closets?

 

[burtsbees]

I would say the computer where the ODBC app resides, or the app itself. Is it a Windows ODBC app, or some other database? Have you checked the forums for that company?

Burt

 

[peterlyttle]

I cant see any errors on any of the Port Chan uplinks, are there any advanced commands I can run to check in more detail? Yes Spanning tree is running across the links.

Burtsbees: We have it happening on multiple servers running different software and have raised support requests with the software manufacturers who say its not the software.

 

[burtsbees]

You said...
"Here is the interface of the server that is noticing the issue"
That indicates one server. Is the interface you posted the only interface that has been used to connect the servers, like on at a time? If so, try a different port---you do have on interface reset on that port. Also, you said...
"(we have swapped the edge switches already to rule them out).", so I would still say it's the software.

Burt

 

[peterlyttle]

Sorry I worded it poorly, its happening on multiple servers running different bits of software (each of these servers have been moved to other ports for testing) The only thing that hasn't been swapped out is the backbone.

Cheers,
Pete