Can anyone explain to me why, when you create an SVI (interface vlan10) on a Catalyst switch, the vlan interface doesn't actually come up/up until a port goes live on that switch?
This is more of a curiosity than a problem.
Because the SVI is a virtual interface but you want it to behave like a physical L3 routed interface. A physical interface will go down if the other end of the link dies but that wouldn't affect an SVI. So to emulate what the physical interface would do Cisco use something called autostate on the SVI which keeps track on whether any physical ports are active for the vlan, including trunk links.
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.