3745 FastEthernet interface problem

nigelt · ‎09-18-2005

We are getting an UPDOWN message for the FastEthernet interface of a 3745. The message is issued every 10 minutes (exactly) and indicates the interface is UP. We never see the interface go down. I have done all the obvious things like change the cable, change the switch port it connects to and reload the router. The problem persists. Any ideas?

thisisshanky · ‎09-18-2005

Can you paste the exact message (wait for 10 min intervals and get the output in your next post). I am trying to figure out what kind of severity the syslog message has. So is this affecting traffic passing through that interface ?

Sankar Nair
UC Solutions Architect
Pacific Northwest | CDW
CCIE Collaboration #17135 Emeritus

nigelt · ‎09-18-2005

Here are some sample messages:

Sep 19 00:07:58 hq3745a.rop.org.om 5891: Sep 19 00:07:57: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up

Sep 19 00:17:58 hq3745a.rop.org.om 5892: Sep 19 00:17:57: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up

Sep 19 00:27:58 hq3745a.rop.org.om 5893: Sep 19 00:27:57: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up

Sep 19 00:37:58 hq3745a.rop.org.om 5894: Sep 19 00:37:57: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up

In terms of performance, traffic is flowing normally.

thisisshanky · ‎09-18-2005

Does moving the config to another interface and use that interface to pass traffic solve the problem (considering you have already tried changing cable, interface on switch etc ) ?

I am wondering if its a h/w problem. Can you also paste a sh version.

Sankar Nair
UC Solutions Architect
Pacific Northwest | CDW
CCIE Collaboration #17135 Emeritus

nigelt · ‎09-18-2005

I intend to try using FastEthernet f0/1 tomorrow when I can make the change without impacting users. My thinking is also that this may be a hardware problem.

Here is the output from show ver:

Cisco Internetwork Operating System Software

IOS (tm) 3700 Software (C3745-ENTBASE-M), Version 12.3(13a), RELEASE SOFTWARE (f

c2)

Technical Support: http://www.cisco.com/techsupport

Compiled Mon 25-Apr-05 19:24 by ssearch

Image text-base: 0x60008AF4, data-base: 0x614A0000

ROM: System Bootstrap, Version 12.2(8r)T2, RELEASE SOFTWARE (fc1)

ROM: 3700 Software (C3745-ENTBASE-M), Version 12.3(13a), RELEASE SOFTWARE (fc2)

HQ3745A uptime is 1 hour, 57 minutes

System returned to ROM by reload at 06:42:54 AST Mon Sep 19 2005

System restarted at 06:45:22 AST Mon Sep 19 2005

System image file is "flash:c3745-entbase-mz.123-13a.bin"

cisco 3745 (R7000) processor (revision 2.0) with 245760K/16384K bytes of memory.

Processor board ID JHY0749K3H3

R7000 CPU at 350MHz, Implementation 39, Rev 3.3, 256KB L2, 2048KB L3 Cache

Bridging software.

X.25 software, Version 3.0.0.

Primary Rate ISDN software, Version 1.1.

Channelized E1, Version 1.0.

2 FastEthernet/IEEE 802.3 interface(s)

36 Serial network interface(s)

6 Channelized E1/PRI port(s)

DRAM configuration is 64 bits wide with parity disabled.

151K bytes of non-volatile configuration memory.

31744K bytes of ATA System CompactFlash (Read/Write)

Configuration register is 0x2102

nigelt · ‎09-20-2005

We moved the connection to FastEthernet0/1 and are still getting the messages. We will now seek hardware assistance from our supplier.

nigelt · ‎10-12-2005

Cause of problem discovered

I have finally discovered the cause of this problem, if not a solution - but not before it brought the Fast Ethernet interface down during prime shift. Anyway the culprit was a rougue server running IBM Director. This server was doing a client discovery every 10 minutes hammering the routers ethernet interface with over 2500 packets a second. Why this bought the ethernet interface down needs to be investigated. Note it effected both the production router and a backup router we also tried in the same way.