Cisco 2950 & Other device

[deltaserver403]

Dear all.

I need ur help regarding below problem.

We recently installed 2950 L2 24 port switch,one of the prot is connected to ADSL modem , the ADSL modem Lan port is auto sensing 10/100MBPS unmanged,

always the LAN port of ADSL modem get hangs, we changed to other ports of Cisco 2950 but same thing happnes.
When we connect ADSL lan port to 3 COM switch it works fine.

what is going wrong here,pls check the cisco Lan port details.
FastEthernet0/24 is up, line protocol is up (connected)
Hardware is Fast Ethernet, address is 0016.c811.4198 (bia 0016.c811.4198)
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 00:00:06, 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 1000 bits/sec, 2 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
109054 packets input, 41347182 bytes, 0 no buffer
Received 76617 broadcasts (0 multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 875 multicast, 0 pause input
0 input packets with dribble condition detected
34949 packets output, 5417694 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
Switch#
Pls anybody has this problem how you sorted it out

Thanks
DS

 

[jneiberger]

Does the port work for a while and then hang, or does it never work at all? If it works for a while and then stops working, how long does it work before it hangs?

 

[NettableWalker]

Have you got that port configured as a trunk? if the router sends anything that looks like a BPDU the switch will block the port.

Have a look at your logs with "Show log" and see if anyhting refers to blocking the port.

MCP,CCA, Net+, 1 quarter CCNP...

 

[robertjo24]

Something to try,
The next time it hanges, go to the switch interface and issue a "SHUT" then "NO SHUT" command. See if it restores.

On the Cisco switch interface facing the ADSL modem, set the speed to 100, and the duplex to full. Also set switchport mode access. The 2950's will sometimes have difficulties syncing with non Cisco devices. It could work a while, then quit for no identifiable reason.

 

[jneiberger]

The line also might be experiencing intermittent errors, even though the output of your "show" command does not show any. If the Cisco switch has "err-disable" turned on, which it does by default, then the switch will shutdown the port after a certain number of errors.

Try disabling the "err-disable" feature and see if that helps.