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Beginner

ISDN back up...please check

We have an ISDN link between 2 locations.

but when we tried to ping doesn't go thru

with each other...

Can please someone check if there7s a problem on the config??

We're not sure yet if it will work or not

if it happens that the main line is down.

Here's the config.i hope this is enough

***Site A****

interface BRI0/0

description ISDN_Call back_server

ip address 192.168.121.245 255.255.255.252

ip access-group 140 out

encapsulation ppp

load-interval 30

dialer idle-timeout 0

dialer map ip 192.168.121.246 name p***** class dial1 *********46756098

dialer hold-queue 100

dialer load-threshold 3 outbound

dialer callback-secure

isdn switch-type ***

no keepalive

no cdp enable

ppp callback accept

***Site B***

interface BRI0/3/0

description Backup_From _B

ip address 192.168.121.246 255.255.255.252

ip access-group 130 out

encapsulation ppp

load-interval 30

dialer idle-timeout 30 either

dialer map ip 192.168.121.245 name p***** *******163506

dialer hold-queue 100

dialer load-threshold 1 outbound

dialer-group 1

isdn switch-type basic-net3

isdn fast-rollover-delay 5

no keepalive

no fair-queue

no cdp enable

ppp callback request

ppp authentication chap

ppp multilink

Thanks

1 ACCEPTED SOLUTION

Accepted Solutions
Hall of Fame Master

Re: ISDN back up...please check

Jayson

I thought that I had already explained it. But let me try it again in a slightly different way. The router will only activate the ISDN when a packet matches the dialer list (which uses an access list to identify the traffic). Since there is no permit in the access list for a packet whose source address is the BRI, then a ping from the BRI to the other BRI does not match and the BRI will not activate. If you want to be able to test by ping from BRI to BRI then you need to add a statement in the access list to permit that host to host traffic.

HTH

Rick

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View solution in original post

25 REPLIES 25
Highlighted
Beginner

Re: ISDN back up...please check

Hi,

Please check the link below for more information on how to configure and ISDN link.

http://www.cisco.com/en/US/tech/tk801/tk379/technologies_configuration_example09186a0080094091.shtml

Let me know if it helps.

RG

Hall of Fame Master

Re: ISDN back up...please check

Jayson

It would be helpful if we had more of the router config. The title of the post indicates ISDN back up and it would be helpful to know if the ISDN is configured as a backup interface for some primary interface or is configured with dialer watch for its activation, or is configured with floating static routes for its activation. If you provide more config detail we might understand the problem better and be able to give you a better suggestion.

If the ISDN is configured as a backup-interface for some primary interface then this may be normal behavior. The backup interface will be in standby state and will not make a call or answer a call unless there is a failure on the primary interface (and an interface shutdown will not start the backup interface). The output of show isdn status would help us see whether this is the issue or not.

I do see a couple of things in the config to comment about. I see ppp authentication chap on Site B but no ppp authentication on Site A. I believe that both sites need ppp authentication.

I see that Site B has ppp multilink but I do not see multilink on Site A. I believe that there should be consistency between the sites about this.

I see that Site B is configured with a dialer-group but that Site A is not. Dialer-group is essential to initiating a call. On that basis I have seen some people configured dialer-group on the router to initiate the call and not configure dialer-group on a router that they want to be an "answer only" (not initiate). But dialer-group is also important in resetting the inactivity timeout and avoiding dropping calls before it should. If a router does not have dialer-group it will never reset the inactivity timer and when that timer expires it will drop the call. A much better way to make a router be answer only is to not put a phone number into its dialer map.

The callback functionality can be difficult. If you remove the callback parts of the config on both sites (temporarily for testing purposes), does the router then be able to place the call?

HTH

Rick

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By doing so, and until end of January, you are helping Doctors Without Borders
Beginner

Re: ISDN back up...please check

Hi Rick...

Thank you very much for the attention.

I have the config for both sides.

*******Site A******

class-map match-all Data

match ip precedence 2

class-map match-all Voice

match ip precedence 5

class-map match-all Maintenance

match ip precedence 6

!

!

policy-map LLQ24ch

class Voice

priority 624

class Data

bandwidth 832

class Maintenance

bandwidth 48

class class-default

bandwidth 200

random-detect

policy-map FE_Precedence

class class-default

shape average 4000000

service-policy LLQ24ch

!

!

!

!

interface Loopback0

description For_voice_session_target_********

ip address 192.168.121.241 255.255.255.255

!

interface FastEthernet0/0

description to LAN

ip address 192.168.120.252 255.255.255.0

ip policy route-map Precedence

duplex auto

speed auto

no cdp enable

!

interface BRI0/0

description ISDN_Call back_server

ip address 192.168.121.245 255.255.255.252

ip access-group 140 out

encapsulation ppp

load-interval 30

dialer idle-timeout 0

dialer map ip 192.168.121.246 name SiteB class dial1 *********446756098

dialer hold-queue 100

dialer load-threshold 3 outbound

dialer callback-secure

isdn switch-type ntt

no keepalive

no cdp enable

ppp callback accept

!

interface FastEthernet0/1

description to WAN

bandwidth 4000

ip address 192.168.121.1 255.255.255.252

speed 100

full-duplex

no cdp enable

service-policy output FE_Precedence

!

router bgp 65000

no synchronization

no bgp log-neighbor-changes

network 6.0.0.0 mask 255.255.254.0

network 10.0.0.0

network 30.0.0.0 mask 255.255.224.0

network 172.16.0.0 mask 255.252.0.0

network 172.28.0.0

network 172.30.0.0 mask 255.254.0.0

network 192.168.0.0 mask 255.255.224.0

network 192.168.52.0 mask 255.255.252.0

network 192.168.56.0 mask 255.255.252.0

network 192.168.80.0

network 192.168.120.0

network 192.168.121.17 mask 255.255.255.255

network 192.168.128.0 mask 255.255.128.0

network 198.179.161.0

neighbor 192.168.121.2 remote-as 11158

neighbor 192.168.121.2 soft-reconfiguration inbound

no auto-summary

!

ip local policy route-map Precedence

no ip http server

ip classless

ip route 6.0.0.0 255.255.254.0 192.168.120.254

ip route 10.0.0.0 255.0.0.0 192.168.120.254

ip route 30.0.0.0 255.255.224.0 192

ip route 192.168.0.0 255.255.224.0 192.168.120.254

ip route 192.168.52.0 255.255.252.0 192.168.120.254

ip route 192.168.56.0 255.255.252.0 192.168.120.254

ip route 192.168.60.0 255.255.255.0 192.168.121.246 200 name SiteB_Backup

ip route 192.168.121.253 255.255.255.255 192.168.121.2 name maintenance_router

ip route 192.168.128.0 255.255.128.0 192.168.120.254

ip route 198.179.161.0 255.255.255.0 192.168.120.254

!

!

!

map-class dialer dial1

dialer callback-server username

access-list 1 permit 192.168.121.0 0.0.0.255

access-list 100 permit tcp any any eq 1720

access-list 100 permit tcp any eq 1720 any

access-list 110 permit ip host 172

access-list 120 permit tcp any any eq bgp

access-list 120 permit tcp any eq bgp any

access-list 130 permit ip any any

access-list 140 permit ip 192.168.52.0 0.0.0.255 192.168.60.

access-list 140 permit ip 192.168.52.0 0.0.0.255 host 192.

access-list 140 permit ip 192.168.52.0 0.0.0.255 host 192.1

access-list 140 permit ip 192.168.56.0 0.0.0.255 192.168.60.6

access-list 140 permit ip 192.168.56.0 0.0.0.255 host 192.1

access-list 140 permit ip 192.168.56.0 0.0.0.255 host 192.

access-list 140 permit ip host 192.168.121.245 host 192.168

no cdp run

!

route-map Precedence permit 100

match ip address 100

set ip precedence critical

!

route-map Precedence permit 110

match ip address 110

set ip precedence immediate

!

route-map Precedence permit 120

match ip address 120

set ip precedence internet

!

route-map Precedence permit 130

match ip address 130

set ip precedence routine

Beginner

Re: ISDN back up...please check

****SiteB****

policy-map LLQ4ch

class Voice

priority 104

class Maintenance

bandwidth 16

class class-default

fair-queue

random-detect

!

!

!

!

interface FastEthernet0/0

description to LAN

ip address 192.168.60.254 255.255.255.0

ip policy route-map Precedence

duplex auto

speed auto

no cdp enable

!

interface FastEthernet0/1

no ip address

shutdown

duplex auto

speed auto

no cdp enable

!

interface Serial0/2/0

description to WAN

bandwidth 1024

ip address 192.168.121.49 255.255.255.252

service-policy output LLQ4ch

encapsulation ppp

no cdp enable

!

interface BRI0/3/0

description Backup_From _SiteB

ip address 192.168.121.246 255.255.255.252

ip access-group 130 out

encapsulation ppp

load-interval 30

dialer idle-timeout 30 either

dialer map ip 192.168.121.245 name **** *******163506

dialer hold-queue 100

dialer load-threshold 1 outbound

dialer-group 1

isdn switch-type basic-net3

isdn fast-rollover-delay 5

no keepalive

no fair-queue

no cdp enable

ppp callback request

ppp authentication chap

ppp multilink

!

router bgp 65000

no synchronization

no bgp log-neighbor-changes

network 192.168.60.0

neighbor 192.168.121.50 remote-as 11158

neighbor 192.168.121.50 soft-reconfiguration inbound

no auto-summary

!

ip local policy route-map Precedence

ip classless

ip route 192.168.52.0 255.255.252.0 192.168.121.245 200 name LAN_BackUp1

ip route 192.168.56.0 255.255.252.0 192.168.121.245 200 name LAN_BackUp2

!

no ip http server

no ip http secure-server

!

!

access-list 1 permit 192.168.121.0 0.0.0.255

access-list 100 permit tcp any any eq 1720

access-list 100 permit tcp any eq 1720 any

access-list 110 permit tcp any any eq bgp

access-list 110 permit tcp any eq bgp any

access-list 120 permit ip 192.168.60.64 0.0.0.3 192.168.52.0 0.0.0.255

access-list 130 permit ip 192.168.60.64 0.0.0.3 192.168.52.0 0.0.0.255

access-list 130 permit ip 192.168.60.64 0.0.0.3 192.168.56.0 0.0.0.255

access-list 130 permit ip host 192.168.60.70 192.168.52.0 0.0.0.255

access-list 130 permit ip host 192.168.60.70 192.168.56.0 0.0.0.255

access-list 130 permit ip host 192.168.60.224 192.168.52.0 0.0.0.255

access-list 130 permit ip host 192.168.60.224 192.168.56.0 0.0.0.255

access-list 130 permit ip host 192.168.121.246 host 192.168.121.245

access-list 199 permit ip any any

dialer-list 1 protocol ip list 120

snmp-server community ****** RO

snmp-server enable traps tty

no cdp run

route-map Precedence permit 100

match ip address 100

set ip precedence critical

!

route-map Precedence permit 110

match ip address 110

set ip precedence internet

!

route-map Precedence permit 199

match ip address 199

set ip precedence routine

Hall of Fame Master

Re: ISDN back up...please check

Jayson

Thanks for the additional information. I believe that it is helpful in better understanding what is going on in your situation. Here are some of the things that I see in it:

- I do not see any configuration of backup-interface so my question about possibly being in standby state is not the issue.

- Site A does have a floating static route for the LAN subnet of B pointing to the ISDN so if the primary route for the LAN at B (which I assume would be learned via BGP) is removed then A will use ISDN to try to get to B. It looks like this should work ok.

- As I mentioned before Site A does not have a dialer group configured so it is not able to initiate a connection to B. It can only answer when B attempts to initiate a connection. If this is what was intended, then this is not a problem - other than the fact that it will not reset the inactivity timer.

- There are several things in the config at B that puzzle me. There are 2 floating static routes on B which point to the ISDN to A. But neither of them is for the subnet at A. I am not clear why you are routing 192.168.52.0 and 192.168.56.0 to A but not routing the subnet at A.

- I believe that the dialer list at B is a problem. This is what allows B to initiate a call over the ISDN. The dialer list only allows 4 IP addresses as the source address (192.168.60.64, .65, .66, and .67) and only allows it to destinations in 192.168.52.0. If your attempt to test by using ping was sourced from one of the four addresses and if the destination of the ping was in 192.168.52.0 then it looks to me like the ISDN should have worked. And if the ping was not from that source and to that destination then the dialer list is the reason that ISDN did not work.

You know this environment and we do not. Perhaps it makes sense to you but to me it looks like a problem.

HTH

Rick

If you found this post helpful, please let the community know by clicking the helpful button!
By doing so, and until end of January, you are helping Doctors Without Borders
Beginner

Re: ISDN back up...please check

Hi Rick

Thank you for the attention.

I understand the dialgroup...if no packets from the host in the dialgroup, then the back will remain down...that's when the main link goes down.

What we're trying to initiate is to check if the back up works ok...and we tried it by ping test.

from site B, source will be the ip add of

site B's BRI port and destination is the Bri port of Site A.

The problem is the ping won't go thru..

That's what's questioning me...

what do you think???

Thank you very much

i really appreciate it...

Hall of Fame Master

Re: ISDN back up...please check

Jayson

I thought that I had already explained it. But let me try it again in a slightly different way. The router will only activate the ISDN when a packet matches the dialer list (which uses an access list to identify the traffic). Since there is no permit in the access list for a packet whose source address is the BRI, then a ping from the BRI to the other BRI does not match and the BRI will not activate. If you want to be able to test by ping from BRI to BRI then you need to add a statement in the access list to permit that host to host traffic.

HTH

Rick

If you found this post helpful, please let the community know by clicking the helpful button!
By doing so, and until end of January, you are helping Doctors Without Borders

View solution in original post

Beginner

Re: ISDN back up...please check

Rick,

Thanks...

I understand now....

I almost laugh when I checked the config again

and noticed that...

looks like I was just looking too far...

It was really helpful..

very kind of you...

again..thanks for the time...

Hall of Fame Master

Re: ISDN back up...please check

Jayson

I am glad that my suggestions were helpful in understanding and resolving your issue. Sometimes it is the really simple things that become hard to recognize.

Thank you for using the rating system to indicate that your issue was resolved (and thanks for the rating). It makes the forum more useful when people can read about an issue and can know that responses were successful in understanding and resolving the issue.

The forum is an excellent place to learn Cisco networking. I encourage you to continue your participation in the forum.

HTH

Rick

If you found this post helpful, please let the community know by clicking the helpful button!
By doing so, and until end of January, you are helping Doctors Without Borders
Beginner

Re: ISDN back up...please check

Rick,

here's the full config for both locations.

Thanks

***Site A****

version 12.3

service timestamps debug datetime msec localtime show-timezone

service timestamps log datetime msec localtime show-timezone

service password-encryption

!

hostname *******

!

boot-start-marker

boot-end-marker

!

logging buffered 10000 debugging

enable secret

!

no network-clock-participate slot 1

no network-clock-participate wic 0

voice-card 1

!

no aaa new-model

ip subnet-zero

ip cef

!

!

no ip domain lookup

!

isdn switch-type *****

!

!

!

!

!

!

!

!

!

!

!

username **** password

!

!

controller T1 1/0

framing esf

linecode b8zs

cablelength short 133

ds0-group 0 timeslots 1-24 type e&m-immediate-start

!

class-map match-all Data

match ip precedence 2

class-map match-all Voice

match ip precedence 5

class-map match-all Maintenance

match ip precedence 6

!

!

policy-map LLQ24ch

class Voice

priority 624

class Data

bandwidth 832

class Maintenance

bandwidth 48

class class-default

bandwidth 200

random-detect

policy-map FE_Precedence

class class-default

shape average 4000000

service-policy LLQ24ch

!

!

!

!

interface Loopback0

description For_voice_session_target_

ip address 192.168.121.241 255.255.255.255

!

interface FastEthernet0/0

description to LAN

ip address 192.168.120.252 255.255.255.0

!

interface BRI0/0

description ISDN_Call back_server

ip address 192.168.121.245 255.255.255.252

ip access-group 140 out

encapsulation ppp

load-interval 30

dialer idle-timeout 0

dialer map ip 192.168.121.246 name SiteB class dial1 **8446756098

dialer hold-queue 100

dialer load-threshold 3 outbound

dialer callback-secure

isdn switch-type ***

no keepalive

no cdp enable

ppp callback accept

!

interface FastEthernet0/1

description to SiteA LAN

bandwidth 4000

ip address 192.168.121.1 255.255.255.252

speed 100

full-duplex

no cdp enable

service-policy output FE_Precedence

!

router bgp 65000

no synchronization

no bgp log-neighbor-changes

network 6.0.0.0 mask 255.255.254.0

network 10.0.0.0

network 30.0.0.0 mask 255.255.224.0

network 172.16.0.0 mask 255.252.0.0

network 172.28.0.0

network 172.30.0.0 mask 255.254.0.0

network 192.0.0.0 mask 255.255.0.0

network 192.1.0.0 mask 255.255.0.0

network 192.168.0.0 mask 255.255.224.0

network 192.168.52.0 mask 255.255.252.0

network 192.168.56.0 mask 255.255.252.0

network 192.168.80.0

network 192.168.120.0

network 192.168.121.17 mask 255.255.255.255

network 192.168.128.0 mask 255.255.128.0

network 198.179.161.0

neighbor 192.168.121.2 remote-as 11158

neighbor 192.168.121.2 soft-reconfiguration inbound

no auto-summary

!

ip local policy route-map Precedence

no ip http server

ip classless

ip route 6.0.0.0 255.255.254.0 192.168.120.254

ip route 10.0.0.0 255.0.0.0 192.168.120.254

ip route 30.0.0.0 255.255.224.0 192.168.120.254

ip route 172.16.0.0 255.252.0.0 192.168.120.254

ip route 172.28.0.0 255.255.0.0 192.168.120.254

ip route 172.30.0.0 255.254.0.0 192.168.120.254

ip route 192.0.0.0 255.255.0.0 192.168.120.254

ip route 192.1.0.0 255.255.0.0 192.168.120.254

ip route 192.168.0.0 255.255.224.0 192.168.120.254

ip route 192.168.52.0 255.255.252.0 192.168.120.254

ip route 192.168.56.0 255.255.252.0 192.168.120.254

ip route 192.168.60.0 255.255.255.0 192.168.121.246 200 SiteB Backup

ip route 192.168.80.0 255.255.255.0 192.168.120.254

ip route 192.168.120.0 255.255.255.0 192.168.120.254

ip route 192.168.121.17 255.255.255.255 192.168.120.254

ip route 192.168.121.253 255.255.255.255 192.168.121.2 name maintenance

ip route 192.168.128.0 255.255.128.0 192.168.120.254

ip route 198.179.161.0 255.255.255.0 192.168.120.254

Beginner

Re: ISDN back up...please check

!

!

!

map-class dialer dial1

dialer callback-server username

access-list 1 permit 192.168.121.0 0.0.0.255

access-list 100 permit tcp any any eq 1720

access-list 100 permit tcp any eq 1720 any

access-list 110 permit ip host 172.16.0.1 any

access-list 110 permit ip host 172.17.0.1 any

access-list 110 permit ip any host 172.29.40.1

access-list 120 permit tcp 192.168.121.0 0.0.0.255 eq telnet any

access-list 120 permit tcp 192.168.121.0 0.0.0.255 any eq telnet

access-list 120 permit icmp host 192.168.121.1 any

access-list 120 permit icmp host 192.168.120.252 any

access-list 120 permit tcp any any eq bgp

access-list 120 permit tcp any eq bgp any

access-list 130 permit ip any any

access-list 140 permit ip 192.168.52.0 0.0.0.255 192.168.60.64 0.0.0.3

access-list 140 permit ip 192.168.52.0 0.0.0.255 host 192.168.60.70

access-list 140 permit ip 192.168.52.0 0.0.0.255 host 192.168.60.224

access-list 140 permit ip 192.168.56.0 0.0.0.255 192.168.60.64 0.0.0.3

access-list 140 permit ip 192.168.56.0 0.0.0.255 host 192.168.60.70

access-list 140 permit ip 192.168.56.0 0.0.0.255 host 192.168.60.224

access-list 140 permit ip host 192.168.121.245 host 192.168.121.246

no cdp run

!

route-map Precedence permit 100

match ip address 100

set ip precedence critical

!

route-map Precedence permit 110

match ip address 110

set ip precedence immediate

!

route-map Precedence permit 120

match ip address 120

set ip precedence internet

!

route-map Precedence permit 130

match ip address 130

set ip precedence routine

!

snmp-server community

snmp-server enable traps tty

!

voice-port 1/0:0

input gain -6

output attenuation 6

cptone

timeouts initial 5

timeouts interdigit 3

!

!

!

!

dial-peer cor custom

!

!

!

Beginner

Re: ISDN back up...please check

*******Site B*****

interface FastEthernet0/0

description to LAN

ip address 192.168.60.254 255.255.255.0

ip policy route-map Precedence

duplex auto

speed auto

no cdp enable

!

interface FastEthernet0/1

no ip address

shutdown

duplex auto

speed auto

no cdp enable

!

interface Serial0/2/0

description to WAN

bandwidth 1024

ip address 192.168.121.49 255.255.255.252

service-policy output LLQ4ch

encapsulation ppp

no cdp enable

!

interface BRI0/3/0

description FromSiteB

ip address 192.168.121.246 255.255.255.252

ip access-group 130 out

encapsulation ppp

load-interval 30

dialer idle-timeout 30 either

dialer map ip 192.168.121.245 **9163506

dialer hold-queue 100

dialer load-threshold 1 outbound

dialer-group 1

isdn switch-type basic-net3

isdn fast-rollover-delay 5

no keepalive

no fair-queue

no cdp enable

ppp callback request

ppp authentication chap

ppp multilink

!

router bgp 65000

no synchronization

no bgp log-neighbor-changes

network 192.168.60.0

neighbor 192.168.121.50 remote-as 11158

neighbor 192.168.121.50 soft-reconfiguration inbound

no auto-summary

!

ip local policy route-map Precedence

ip classless

ip route 192.168.52.0 255.255.252.0 192.168.121.245 200 name _LAN_BackUp1

ip route 192.168.56.0 255.255.252.0 192.168.121.245 200 name _LAN_BackUp2

!

no ip http server

no ip http secure-server

!

!

access-list 1 permit 192.168.121.0 0.0.0.255

access-list 100 permit tcp any any eq 1720

access-list 100 permit tcp any eq 1720 any

access-list 110 permit tcp 192.168.121.0 0.0.0.255 eq telnet any

access-list 110 permit tcp 192.168.121.0 0.0.0.255 any eq telnet

access-list 110 permit icmp host 192.168.121.49 any

access-list 110 permit icmp host 192.168.60.254 any

access-list 110 permit tcp any any eq bgp

access-list 110 permit tcp any eq bgp any

access-list 120 permit ip 192.168.60.64 0.0.0.3 192.168.52.0 0.0.0.255

access-list 120 permit ip 192.168.60.64 0.0.0.3 192.168.56.0 0.0.0.255

access-list 120 permit ip host 192.168.60.70 192.168.52.0 0.0.0.255

access-list 120 permit ip host 192.168.60.70 192.168.56.0 0.0.0.255

access-list 120 permit ip host 192.168.60.224 192.168.52.0 0.0.0.255

access-list 120 permit ip host 192.168.60.224 192.168.56.0 0.0.0.255

access-list 120 permit ip host 192.168.121.246 host 192.168.121.245

access-list 130 permit ip 192.168.60.64 0.0.0.3 192.168.52.0 0.0.0.255

access-list 130 permit ip 192.168.60.64 0.0.0.3 192.168.56.0 0.0.0.255

access-list 130 permit ip host 192.168.60.70 192.168.52.0 0.0.0.255

access-list 130 permit ip host 192.168.60.70 192.168.56.0 0.0.0.255

access-list 130 permit ip host 192.168.60.224 192.168.52.0 0.0.0.255

access-list 130 permit ip host 192.168.60.224 192.168.56.0 0.0.0.255

access-list 130 permit ip host 192.168.121.246 host 192.168.121.245

access-list 199 permit ip any any

dialer-list 1 protocol ip list 120

snmp-server community ****** RO

snmp-server enable traps tty

no cdp run

route-map Precedence permit 100

match ip address 100

set ip precedence critical

!

route-map Precedence permit 110

match ip address 110

set ip precedence internet

!

route-map Precedence permit 199

match ip address 199

set ip precedence routine

Beginner

Re: ISDN back up...please check

hi Rick...

I just noticed...

I have the ip add of the bri port of the other side at the dialer list....

but ping is NG....???

Thanks

Hall of Fame Master

Re: ISDN back up...please check

Jayson

I see that access list 120 has a bunch of entries added including one that should allow ping from the BRI at B to the BRI at A. The dialer list was an issue before and I believe that it is not the issue now. If ping does not work then we need to look for something else.

I would like to start with the output of show isdn status from both routers. Can you post that?

Assuming that the status looks normal we need to look at some other things to determine why ping is not working. I will list several debugs that may show us the problem. For ease of interpretation I would suggest that you run then one at a time (start the first debug, attempt the ping, gather the debug output, stop that debug and start the next debug, attempt ping, and cycle through the list:

- debug dialer (this will show whether the router believes that it should bring up the ISDN. I would expect it to show attempts at dial activity - if it does not show dial attempts then do not run the other debugs).

- debug isdn q931 (this should show the ISDN dialing activity and whether there are ISDN issues preventing the call)

- debug ppp negotiation (if ISDN dials the call then this will show the router attempting to make the PPP connection)

- debug ppp authentication (if PPP is negotiated this will show whether there are problems in authentication).

Post these debugs and we will see what they show us about the ping not working.

HTH

Rick

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