Help to create frame-relay multilink PPP

[Steph1963]

Hi,

I would like to know if it is possible to build  a frame-relay multiplink PPP on more than one interface. In other words, could we aggregate two serial port and build a single bundle of frame-relay multilink PPP and keep the same map-class frame-relay SHAPE_384K using the following configuration.

I would also like to understand why the following configuration creates virtual-Template and Virtual-access interfaces:

show ip int brief

Virtual-Access1            177.1.101.1     YES TFTP   up                    up

Virtual-Template1          177.1.101.1     YES TFTP   down                  down

Thanks for your help

Stephane

Configuration

class-map match-all VOICE

match ip dscp ef

class-map match-all SIGNALING

match ip dscp cs3

!

policy-map CBWFQ

class VOICE

    priority 48

class SIGNALING

    bandwidth 8

class class-default

    fair-queue

!

interface Serial1/0

no ip address

encapsulation frame-relay

serial restart-delay 0

frame-relay traffic-shaping

!

interface Serial1/0.1 point-to-point

frame-relay interface-dlci 112 ppp Virtual-Template1

  class SHAPE_384K

!

interface Virtual-Template1

bandwidth 384

ip unnumbered Loopback0

ppp multilink

ppp multilink interleave

ppp multilink fragment delay 13

service-policy output CBWFQ

!

map-class frame-relay SHAPE_384K

frame-relay cir 384000

frame-relay bc 3840

frame-relay be 0

frame-relay mincir 384000

[smehrnia]

Hi,

virtual access is a cloned interface, which is created automatically along with the virtual template. as the name of the Virtual-Template implies it is a template used for creating virtual interfaces, whenever u use the template and bind it to an interface n it starts working it creates this virtual access instance.

keep in mind that to make a multilink bundle u need to be able to configure the other end of the connection as MPPP too.

U have to create ur physical FR interfaces, assign class-maps n bind a virtual template to the SVC's u link to be in the bundle:

interface virtual-template X

  no ip address

  ppp multilink

  ppp multilink group 1

and then create the multilink interface and assign ur desired setting to it:

interface multilink X

ip address x.x.x.x

bandwidth xxx

ppp multilink

ppp multilink group 1  .... (same group number)

ppp multilink fragment delay 13

service-policy output CBWFQ

Hope it Helps,

Soroush.

[Steph1963]

Hi Soroush,

Thanks a lot for your reply, a virtual-access is a cloned interface from the virtual-template make sense to me. Can we say that the virtual-access interface can be up or down while virtual-template is always down. What could be the reason for this?

I would like to understand if I can use the following configuration in the case where I want to assing a second interface to the sampe multilink PPP bundle.

interface Serial1/1.1 point-to-point

frame-relay interface-dlci 112 ppp Virtual-Template1

  class SHAPE_384K

I think I am confused about the utilization of a virtual Template. I am not sure when a Virtual Template is required or not. In your configuration example, you are using a virtual template.

interface virtual-template X

  no ip address

  ppp multilink

  ppp multilink group 1

interface multilink X

  ip address x.x.x.x

  bandwidth xxx

  ppp multilink

  ppp multilink group 1  .... (same group number)

  ppp multilink fragment delay 13

  service-policy output CBWFQ

I would assume that the interace configuration would be the following but I am not sure

interface serial1/0/0/1:0

  frame-relay inerface-dlci 100 ppp virtual-template 1

But I have also seen configuration example like the following one with no virtual-template. Why in this case, no virtual-template is require.

interface Multilink1

ip unnumbered Loopback0

ppp multilink

ppp multilink group 1

!

interface Serial1/4

bandwidth 2000

encapsulation ppp

ppp multilink

ppp multilink group 1

!

interface Serial1/5

bandwidth 4000

encapsulation ppp

ppp multilink

ppp multilink group 1

serial restart-delay 0

Thanks for all your help

Stephane

[smehrnia · Accepted solution]

Hey Steph,

virtual-templates, act like template configurations which u can call for different interfaces, to my understanding the virtual access is the resemblance of the bind between the template and a physical interface, i believe because a template is never directly in action it is down, but where it is in effect with a physical interface, the binding (virtual access) comes up up.

here in ur original post i saw that you want to do a multilink on Frame Relay VC's, it is called PPP over Frame Relay, so its DLCI membership in a multilink interface is configured with utilizing virtual templates through the below command:

interface serial1/0/0/1:0

  frame-relay interface-dlci 100 ppp virtual-template 1

in the other config u shared above, those interfaces are originally using PPP encapsulation, it is different from PPPoFR which u deal with virtual circuits and per DLCI.

HTH

plz Rate helpful posts.

Soroush.