Interface Virtual-Access 1

stacey.robinette · ‎09-16-2009

What is an Interface Virtual-Access1? I recently noticed this interface on a 2800 series router after installing a second T1 circuit and creating a Multilink combining both my T1s. I hadn't noticed this interface before. What is its purpose?

paolo bevilacqua · ‎09-16-2009

Comes up cloned from you multilink interface other template. This because you can have multiple VA instances from a same template.

Peter Paluch · ‎09-16-2009

Hello,

A Virtual-Access interface is an interface that is cloned (instantiated) from another interface, usually a Virtual-Template or Dialer. The relation between an Virtual-Template or Dialer interface and a Virtual-Access is quite similar to a difference between a class and the object in the object programming paradigm. The Dialer or Virtual-Template interfaces represent a template for creation of individual virtual interfaces. However, these are only templates. Whenever the template should start working as a real interface, it is instantiated into a Virtual-Access interface that is the actual live virtual interface through which packets are processed and routed.

You cannot configure the Virtual-Access interfaces directly. They are not really visible in your configuration and they are created and deleted on the fly. If you need to change the Virtual-Access settings, you always need to change the settings on the template interface from which the Virtual-Access has been cloned. The "show interfaces" will tell you what interface was used as a template for creating the particular Virtual-Access interface.

Best regards,

Peter

stacey.robinette · ‎09-16-2009

Thanks Peter,

Your explanation was very helpful.

YANGCCIE4 · ‎09-16-2009

virtual-template and virtual-access are created at the same time.

virtual-template is function as the interface.

here is my 1 cent...

interface Serial1/0

no ip address

encapsulation frame-relay

shutdown

serial restart-delay 0

frame-relay interface-dlci 103 ppp Virtual-Template1

no clns route-cache

end

r1#sh ip int brief

Interface IP-Address OK? Method Status Protocol

FastEthernet0/0 unassigned YES unset administratively down down

Serial1/0 unassigned YES unset administratively down down

Serial1/1 unassigned YES unset administratively down down

Serial1/2 unassigned YES unset administratively down down

Serial1/3 unassigned YES unset administratively down down

Virtual-Access1 unassigned YES TFTP down down

Virtual-Template1 unassigned YES TFTP down down

Loopback0 unassigned YES unset up up

r1#

r1