Cisco 3560 port shutting down
I have a cisco 3560 switch port 23 connected to a cisco ESW-540 switch port 3 using straight through patch cable. The port on the 3560 keeps shutting down after about 4 hours. To get link up have to perform shut/ noshut on 3560 port 23. What could cause this port to keep shutting down?
Software/Hardware used:
Cisco 3560 & cisco ESW-540
Software/Hardware used:
Cisco 3560 & cisco ESW-540
ASKED:
June 18, 2010 1:20 PM
UPDATED:
June 18, 2010 2:22 PM
Answer Wiki:
There are lots of reason why IOS will shutdown an interface but basically it is due to the software detecting an error condition. It could be that a cable is out of specification (either too long, the wrong type, or defective). Alternatively it could also be software (misconfiguration) related such as:
Duplex mismatch
Port channel misconfiguration
BPDU guard violation
UniDirectional Link Detection (UDLD) condition
Late-collision detection
Link-flap detection
Security violation
Port Aggregation Protocol (PAgP) flap
Layer 2 Tunneling Protocol (L2TP) guard
DHCP snooping rate-limit
Incorrect GBIC / Small Form-Factor Pluggable (SFP) module or cable
Address Resolution Protocol (ARP) inspection
Inline power
Post the exact syslog message if you have it, which will look something like this:
PM-SP-4-ERR_DISABLE: udld error detected on Gi4/1, putting Gi4/1 in err-disable state.
You can find the messages in the log by typing "show log"
To see all answers submitted to the Answer Wiki: View Answer History.
what is BPDU, what does it to and where can I get more info on the settings?
what is BPDU…
Best way to find is to type [ BPDU ] into a Google search box (or other search engine) and read the pages at the resulting link addresses. If you have problems over parts of it, they might be good to ask about in a question here.
Tom