There's a descrepancy in the spantree portcost setting between the 2 config files on our cat 5000 taking within a 4 month period. To the best of my knowledge, no one manually changed them. Are they somehow getting auto reset depending on what is plugged in to the ports?
What changed was the cost for the ports: for example, in the old config, the portcost of a port 6/1 was "19" and in the new config it was set to "100". The software version is 4.5 (13) and either a Netware 4.1 or NT 4.0 server were plugged into these ports.
STP cost of 19 indicates a 100-megabit-per-second link speed, Fast Ethernet connection. Cost of 100 is for a 10-megabit-per-second link speed, Ethernet connection. These are Cisco's newer defaults; you can override these manually, if you want to precisely control how Spanning Tree sorts itself out, which is helpful in a mixed-manufacturer environment. (Not everybody costs their ports the same way.) But an all-Cisco network work fine with the defaults.
My guess is your port 6/1 is a 10/100 port set to autodetect speed and duplex.
Other STP costs in the Ethernet family: 4 is a 1-gigabit-per-second, Gigabit Ethernet connection; and I think 2 is for a 10-gigabit-per-second, 10 Gigabit Ethernet connection.
Cost generally used to be 1000 divided by link speed. This became a problem as speeds approached and then passed Gigabit, since the value passed along had to be an integer. (That is, you can't have a port cost of 0.4 for an OC-48 at 2.5-Gbps.) How would your network tell the difference between a Gig link and a 10-Gig link if they're both rounded to 1? Thus the recosting to the newer values.
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.