1720 FastEthernet strange behaviour (stops working!)

[rtmena]

Hi, I have a 1720 with one WIC1T and one WIC2T cards acting as my border router.

All three serials are working (bandwidth 2048 each).

The fast ethernet is connected via a cross-over cable to my proxy.

Today one strange thing happened. The ethernet of the router stopped working. I could log via console and saw nothing strange (load ok, serials up).

I disconnected the ethernet cable and plugged back in. Even tough I could see the ethernet changing from UP to DOWN and back to UP (console messages) the only way I could make it work was to reboot.

Any ideas of what caused this ?

 

[IPKONFIG]

Sounds like a software bug. If you have access to Cisco TAC, then I'd suggest you upgrade the IOS first.

"I can picture a world without war. A world without hate. A world without fear. And I can picture us attacking that world, because they'd never expect it."
- Jack Handey, Deep Thoughts

 

[rtmena]

Hi, Thanks.

I do not have an account so I am not how can I contact TAC.

This is the output of my show version

Cisco Internetwork Operating System Software
IOS (tm) C1700 Software (C1700-Y-M), Version 12.1(8a), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2001 by cisco Systems, Inc.
Compiled Tue 22-May-01 23:52 by yiyan
Image text-base: 0x80008088, data-base: 0x805ECA74

ROM: System Bootstrap, Version 12.0(3)T, RELEASE SOFTWARE (fc1)

System returned to ROM by power-on
System image file is "flash:c1700-y-mz.121-8a"

cisco 1720 (MPC860) processor (revision 0x601) with 24576K/8192K bytes of memory.
M860 processor: part number 0, mask 32
Bridging software.
X.25 software, Version 3.0.0.
1 FastEthernet/IEEE 802.3 interface(s)
3 Serial(sync/async) network interface(s)
32K bytes of non-volatile configuration memory.
8192K bytes of processor board System flash (Read/Write)

Configuration register is 0x2102

 

[ChrisAC]

Could just be something as simple as a speed/duplex mis-match between the router and the proxy.

Chris.


**********************
Chris Andrew, CCNA, CCSA
chris@iproute.co.uk
**********************

 

[IPKONFIG]

Duplex and Speed mismatches usually causes the interfaces to bounce...not just stop working. That IOS is old, they have 12.2 train out now and you need to find someone who can give you the hook-up.

"I can picture a world without war. A world without hate. A world without fear. And I can picture us attacking that world, because they'd never expect it."
- Jack Handey, Deep Thoughts

 

[digitalrice]

try to change the speed to half-duplex, usually it'll solved the problem.

 

[Blacknight1964]

Rrtmena you are not alone...

Just finnished off a large project to consolidate a number of different networks throughtout 16 sites and consolidating Business/SCADA/VoIP services to one network and one Telco provider. We went with a 1760 and a 4 port WIC-4ESW card and use VLANS/separt port for each separte service. Telco circuits are either T1 Copper or 10Meg Fiber or 100Meg Fiber depending on site. The teleco is providing the complete router support. We currently have the exactly the same problem when for no apparent reason the one Ethernet port stops transmitting data (99% port #2 Scada). It is not flapping, everything show up, when we try to ping devices on the remote network (other side of the 4-port WIC), you can see the ARP table update and the packet go through, on the way back it stops at the port (using packet monitoring tools to capture this). We have extended the Bridge-Timer between VLANs and this has helped and solved 90% of the port shutdown. The simple fix if we loose a port is to ping the router port ie (172.xx.xx.1). The network comes backup and everyone is happy, but it is a real pain in the rear when you have to do this at 3:00am. Here is the kicker, it only happens to the SCADA network, both the Business and VoIP networks stay up and running the whole time. We have been able to make if fail on command by power cycling the router. VoIP, Busiess come up after the power cycle no problem, SCADA stays down unit we ping the Ethernet network Router Port. We have cut a ticket with Cisco and already have the latest IOS with a special Cisco Patch to make the WIC-4ESW work on the 1760. We will see what Cisco says.

Over all I have been very happy with the 1760 and the Telco, except for this little problem, managment have been have been also very understanding, I am saving them $40k per month in telecom charges, that is all they care about.