Solved: frame-relay lab

dhalevi · ‎12-02-2008

Hi All,

Thank you for taking the time to read this. I setup the frame relay lab scenario from the follwoing link,

http://www.cisco.com/warp/public/125/fr_switching.pdf

I would like to modify the configuration so that I can ping from Aton to Prasit without adding a VC between them. I have configured all the dlci's on sub interfaces.

Among the many things that are puzzling me is that I can ping from Spicy to Aton, but not from Spicy to Prasit.

Spicey#ping 3.1.3.3

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 3.1.3.3, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms

Spicey#

May 6 09:21:05.969: IP: s=3.1.3.1 (local), d=3.1.3.3 (Serial0.1), len 100, sending

May 6 09:21:05.973: IP: s=3.1.3.3 (Serial0.1), d=3.1.3.1, len 100, rcvd 2

May 6 09:21:05.973: IP: s=3.1.3.1 (local), d=3.1.3.3 (Serial0.1), len 100, sending

May 6 09:21:05.977: IP: s=3.1.3.3 (Serial0.1), d=3.1.3.1, len 100, rcvd 2

May 6 09:21:05.977: IP: s=3.1.3.1 (local), d=3.1.3.3 (Serial0.1), len 100, sending

May 6 09:21:05.981: IP: s=3.1.3.3 (Serial0.1), d=3.1.3.1, len 100, rcvd 2

May 6 09:21:05.981: IP: s=3.1.3.1 (local), d=3.1.3.3 (Serial0.1), len 100, sending

May 6 09:21:05.989: IP: s=3.1.3.3 (Serial0.1), d=3.1.3.1, len 100, rcvd 2

May 6 09:21:05.989: IP: s=3.1.3.1 (local), d=3.1.3.3 (Serial0.1), len 100, sending

May 6 09:21:05.993: IP: s=3.1.3.3 (Serial0.1), d=3.1.3.1, len 100, rcvd 2

Spicey#

Spicey#ping ip

Target IP address: 3.1.3.2

Repeat count [5]:

Datagram size [100]:

Timeout in seconds [2]:

Extended commands [n]: y

Source address or interface:

May 6 09:24:46.221: IP: s=3.1.3.1 (local), d=255.255.255.255 (Serial0.1), len 52, sending broad/multicast3.1.3.4

Type of service [0]:

Set DF bit in IP header? [no]:

Validate reply data? [no]:

Data pattern [0xABCD]:

Loose, Strict, Record, Timestamp, Verbose[none]:

Sweep range of sizes [n]:

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 3.1.3.2, timeout is 2 seconds:

Packet sent with a source address of 3.1.3.4

May 6 09:24:52.509: IP: s=3.1.3.4 (local), d=3.1.3.2 (Serial0.1), len 100, sending

May 6 09:24:52.513: IP: s=3.1.3.4 (Serial0.1), d=3.1.3.2 (Serial0.1), len 100, rcvd local pkt.

May 6 09:24:54.509: IP: s=3.1.3.4 (local), d=3.1.3.2 (Serial0.1), len 100, sending

May 6 09:24:54.509: IP: s=3.1.3.4 (Serial0.1), d=3.1.3.2 (Serial0.1), len 100, rcvd local pkt.

May 6 09:24:56.509: IP: s=3.1.3.4 (local), d=3.1.3.2 (Serial0.1), len 100, sending

May 6 09:24:56.509: IP: s=3.1.3.4 (Serial0.1), d=3.1.3.2 (Serial0.1), len 100, rcvd local pkt.

May 6 09:24:58.509: IP: s=3.1.3.4 (local), d=3.1.3.2 (Serial0.1), len 100, sending

May 6 09:24:58.509: IP: s=3.1.3.4 (Serial0.1), d=3.1.3.2 (Serial0.1), len 100, rcvd local pkt.

May 6 09:25:00.509: IP: s=3.1.3.4 (local), d=3.1.3.2 (Serial0.1), len 100, sending

May 6 09:25:00.509: IP: s=3.1.3.4 (Serial0.1), d=3.1.3.2 (Serial0.1), len 100, rcvd local pkt

May 6 09:25:00.957: IP: s=3.1.3.2 (Serial0.2), d=255.255.255.255, len 52, rcvd 2.

Success rate is 0 percent (0/5)

Spicey#

Any help is much appreciated.

Doron

Giuseppe Larosa · ‎12-02-2008

Hello Doron,

>> I would like to modify the configuration so that I can ping from Aton to Prasit without adding a VC between them. I have configured all the dlci's on sub interfaces.

you need to add a frame-relay map command for the spoke using the SAME DLCI that you use to reach the hub router.

if you have implemented a FR NBMA if all links are point-to-point you just need ip static routes

Hope to help

Giuseppe

View solution in original post

Giuseppe Larosa · ‎12-02-2008

Hello Doron,

I've reviewed your configuration on Spicey and it is not correct:

interface Serial0.1 point-to-point

ip address 3.1.3.1 255.255.255.0

frame-relay interface-dlci 130

!

interface Serial0.2 point-to-point

ip address 3.1.3.4 255.255.255.0

frame-relay interface-dlci 140

!

If you want to use two distinct point to point subinterfaces you need to use two distinct IP subnets

you are using the same IP subnet 3.1.3.0/24 on both interfaces.

IOS allows you to do this but only one of the two can work the other one not.

Try to modify using

3.1.4.0/24 on the second p-to-p subif and change it also on Parsit.

Note2:

To use a single IP subnet that spans the three routers you need a different configuration on the hub Spicey

int ser0.1 point-to-multipoint

ip address 3.1.3.1 255.255.255.0

frame-relay map ip 3.1.3.2 130 broadcast

frame-relay map ip 3.1.3.3 140 broadcast

!

defining the subif as multipoint the router is ready to use multiple DLCIs but you need to help it in associating the right DLCI to the right device.

(actually an automatic mechanism called inverse ARP exists but the frame-relay map allows to add the broadcast keyword that enables the usage of dynamic routing protocols)

Hope to help

Giuseppe

View solution in original post

Giuseppe Larosa · ‎12-02-2008

Hello Doron,

>> I would like to modify the configuration so that I can ping from Aton to Prasit without adding a VC between them. I have configured all the dlci's on sub interfaces.

you need to add a frame-relay map command for the spoke using the SAME DLCI that you use to reach the hub router.

if you have implemented a FR NBMA if all links are point-to-point you just need ip static routes

Hope to help

Giuseppe

dhalevi · ‎12-02-2008

hi Giuseppe,

Thanks for answering. I am using static routes on the switch.

!

interface Serial0/0

description *** static DCE connection to s1 Parsit

no ip address

encapsulation frame-relay

clock rate 2000000

frame-relay intf-type dce

frame-relay route 150 interface Serial0/1 140

!

interface Serial0/1

description *** static DCE connection to Spicey

no ip address

encapsulation frame-relay

clock rate 2000000

frame-relay intf-type dce

frame-relay route 130 interface Serial3/0 160

frame-relay route 140 interface Serial0/0 150

!

interface Serial3/0

description *** static DCE connection to s1 Aton

no ip address

encapsulation frame-relay

no ip mroute-cache

clock rate 2000000

frame-relay intf-type dce

frame-relay route 160 interface Serial0/1 130

!

When I do the ping I use an extended ping to specify the source address of the subinterface with the correct dlci. This way I am sure that the static route exists for the dlci to get to the router I am trying to ping.

I am using the source IP address 3.1.3.4 which belongs to sub intf s0.2 with dlci 140

The switch has a static route for 140 out s0/0 with dlci 150.

The sub intf I am trying to ping has ip address 3.1.3.2 with dlci 150.

Should work, shouldn't it?

thanks,

Doron

Giuseppe Larosa · ‎12-02-2008

Hello Doron,

I've reviewed your configuration on Spicey and it is not correct:

interface Serial0.1 point-to-point

ip address 3.1.3.1 255.255.255.0

frame-relay interface-dlci 130

!

interface Serial0.2 point-to-point

ip address 3.1.3.4 255.255.255.0

frame-relay interface-dlci 140

!

If you want to use two distinct point to point subinterfaces you need to use two distinct IP subnets

you are using the same IP subnet 3.1.3.0/24 on both interfaces.

IOS allows you to do this but only one of the two can work the other one not.

Try to modify using

3.1.4.0/24 on the second p-to-p subif and change it also on Parsit.

Note2:

To use a single IP subnet that spans the three routers you need a different configuration on the hub Spicey

int ser0.1 point-to-multipoint

ip address 3.1.3.1 255.255.255.0

frame-relay map ip 3.1.3.2 130 broadcast

frame-relay map ip 3.1.3.3 140 broadcast

!

defining the subif as multipoint the router is ready to use multiple DLCIs but you need to help it in associating the right DLCI to the right device.

(actually an automatic mechanism called inverse ARP exists but the frame-relay map allows to add the broadcast keyword that enables the usage of dynamic routing protocols)

Hope to help

Giuseppe

dhalevi · ‎12-03-2008

Thanks Giuseppe!