What are the main causes of a port going into the above state?
I have a small SAN solution, using a Cat 6509. On performing a test backup, the port associated with the client device went into errdisable mode after partially completing a job. The port is set auto speed/duplex.
At first, this feature was implemented to handle special collision situations where the switch detected excessive or late collisions on a port. Excessive collisions occur when a frame is dropped because of encountering 16 collisions in a row. Late collisions occur after every device on the wire should have recognized that the wire was in use. These types of errors could be caused by a cable that is not to specification (too long, wrong type, defective), a bad network interface card (NIC) card (with physical problems, or driver problems), or a port duplex misconfiguration. This last cause is common because of failures to negotiate the speed and duplex properly between two directly connected devices (for example, a NIC card connected to a switch). Only half-duplex connections should ever have collisions in a LAN; due to the Carrier-Sense Multi-Access (CSMA) nature of Ethernet, collisions are normal for half-duplex, as long as they do not exceed a small percentage of traffic.
As the capabilities of the CatOS grew, there were more ways that a port could become error-disabled. Some of these new ways included an EtherChannel misconfiguration, Bridge Protocol Data Unit (BPDU) port-guard violation, UDLD, and other (miscellaneous) causes.
The error-disable function allows the switch to shut down a port when it encounters any of these situations. Remember, a port being error-disabled is not by itself a cause for alarm, as long as one determines and resolves its root cause. An error-disabled port is a symptom of a deeper problem that must be resolved.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.