关于思科2950的一个奇怪问题

创新0824

大家好：
      今天遇到一个很奇怪的问题，请教大家一下
      思科2950-24下接入一个考勤的终端设备，插上后报警:
00:29:14: %LINK-3-UPDOWN: Interface FastEthernet0/19, changed state to up
00:29:16: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/19, changed state to up
00:29:20: %ETHCNTR-3-LOOP_BACK_DETECTED: Keepalive packet loop-back detected on FastEthernet0/19.
00:29:20: %PM-4-ERR_DISABLE: loopback error detected on Fa0/19, putting Fa0/19 in err-disable state
00:29:21: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/19, changed state to down
00:29:22: %LINK-3-UPDOWN: Interface FastEthernet0/19, changed state to down
00:29:48: %PM-4-ERR_RECOVER: Attempting to recover from loopback err-disable state on Fa0/19
00:29:52: %LINK-3-UPDOWN: Interface FastEthernet0/19, changed state to up
00:29:54: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/19, changed state to up
00:30:00: %ETHCNTR-3-LOOP_BACK_DETECTED: Keepalive packet loop-back detected on FastEthernet0/19.
00:30:00: %PM-4-ERR_DISABLE: loopback error detected on Fa0/19, putting Fa0/19 in err-disable state
00:30:01: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/19, changed state to down
00:30:02: %LINK-3-UPDOWN: Interface FastEthernet0/19, changed state to down
00:30:28: %PM-4-ERR_RECOVER: Attempting to recover from loopback err-disable state on Fa0/19
00:30:32: %LINK-3-UPDOWN: Interface FastEthernet0/19, changed state to up
00:30:34: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/19, changed state to up
00:30:40: %ETHCNTR-3-LOOP_BACK_DETECTED: Keepalive packet loop-back detected on FastEthernet0/19.
j交换机里面没有任何配置，当做一个hub来用。
如果试着把keepalive设置为0的时候，所有的MAC都开始从这个19口学习到，出现环路，从而影响其他端口的正常使用。
各位大侠可有解决的办法？

创新0824

自己顶一下吧~~~~

forlend

{:soso_e193:}

liuhuacool

交换机即使你不做任何 配置它也不会是个hub的，而你没做任何配置的话应该会在同一个默认vlan里面，同网络通信是没有问题的。
貌似是19口出环告警，你19底下接的什么呢。

创新0824

liuhuacool 发表于 2013-1-13 18:21
交换机即使你不做任何 配置它也不会是个hub的，而你没做任何配置的话应该会在同一个默认vlan里面，同网络通 ...

一个考勤机！应该是个重端，我听都没听说过的一个东西！

无中生有

disable keepalive 再升级下你的IOS。
这是思科官网查到的解释。
A loopback error occurs when the keepalive packet is looped back to the port that sent the keepalive. The switch sends keepalives out all the interfaces by default. A device can loop the packets back to the source interface, which usually occurs because there is a logical loop in the network that the spanning tree has not blocked. The source interface receives the keepalive packet that it sent out, and the switch disables the interface (errdisable). This message occurs because the keepalive packet is looped back to the port that sent the keepalive:

%PM-4-ERR_DISABLE: loopback error detected on Gi4/1, putting Gi4/1 in
err-disable state
Keepalives are sent on all interfaces by default in Cisco IOS Software Release 12.1EA-based software. In Cisco IOS Software Release 12.2SE-based software and later, keepalives are not sent by default on fiber and uplink interfaces. For more information, refer to Cisco bug ID CSCea46385  (registered customers only) .

The suggested workaround is to disable keepalives and upgrade to Cisco IOS Software Release 12.2SE or later.

小阳不上学

啥也不说了，楼主就是给力！