what causes flapping of uplink interfaces on a Cisco switch

[onyx_oyin]

what causes flapping of uplink interfaces on a Cisco switch?

[InayathUlla Sharieff]

Hi Mojoyinola,

Link flap means that the interface continually goes up and down in a Cisco Switch. The interface is put into the errdisabled state if it flaps more than five times in 10 seconds. The common cause of link flap is a Layer 1 issue such as a bad cable, duplex mismatch, or bad Gigabit Interface Converter (GBIC) card. Look at the console messages or the messages that were sent to the syslog server that state the reason for the port shutdown.

HTH

Regards

Inayath

*plz rate if this info is usefull.

[Leo Laohoo]

You got to provide more information than that. 

Can you post the output to the following commands:

1.  sh logs;

2.  sh version;

3.  sh interface