I would just like to ask how to detect an intermittent line. We are using 4 Fast Ethernet to connect two sites.
The interface won't go to down/down state because all of our FastE interfaces are connected to the media converter of the provider. We have one FastE interface right now which is intermittent. We can see that the link is intermittent by means of ping.
We can't accomodate this kind of interfaces since we are going to use these links for voice traffic.
The issue occurs when Encoded Address Recognition Logic (EARL) is unable to set the CAM aging time for the VLAN to the required number of seconds. Here, the VLAN aging time is already set to fast aging.
When the VLAN is already in fast aging, EARL cannot set the VLAN to fast aging, and aging timer set process is blocked. The default CAM aging time is five minutes, which means that the switch flushes the table of learned MAC addresses every five minutes. This ensures that the MAC address table (the CAM table) contains the most recent entries.
Fast aging temporarily sets the CAM aging time to the number of seconds that the user specifies, and is used in conjunction with the Topology Change Notification (TCN) process. The idea is that when a topology change occurs, this value is necessary to flush the CAM table faster, to compensate for the topology change.
Issue the show cam aging command to check the CAM aging time on the switch. TCNs and fast aging are fairly rare. As a result, the message has a severity level of 3. If the VLANs are frequently in fast aging, check the reason for fast aging.
The most common reason for TCNs is client PCs connected directly to a switch. When you power up or down the PC, the switch port changes state, and the switch starts the TCN process. This is because the switch does not know that the connected device is a PC; the switch only knows that the port has changed the state.
In order to resolve this issue, Cisco has developed the PortFast feature for host ports. An advantage of PortFast is that this feature suppresses TCNs for a host port.
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.