06-12-2003 04:23 AM - edited 03-02-2019 08:05 AM
I am attempting to configure a 1721 router (12.2.13t3) with an ADSL connection and an ISDN backup. Individually both parts of the config work fine, but when I put them together I have been unable to get the backup working. The ATM will go down, and the dialer1 initialises, but does not attempt to dial. Any suggestions would be appreciated.
ip subnet-zero
!
!
isdn switch-type basic-ts013
!
!
!
interface ATM0
bandwidth 1500
no ip address
backup delay 10 120
backup interface Dialer1
no atm ilmi-keepalive
pvc 8/35
encapsulation aal5mux ppp dialer
dialer pool-member 1
!
dsl operating-mode auto
!
interface BRI0
description connected to Internet
no ip address
encapsulation ppp
dialer pool-member 2
isdn switch-type basic-ts013
no cdp enable
!
interface FastEthernet0
ip address x.x.x.x 255.255.255.248
speed auto
!
interface Dialer0
ip address x.x.x.x 255.255.255.0
encapsulation ppp
dialer pool 1
no cdp enable
ppp authentication chap callin
ppp chap hostname ********
ppp chap password ********
!
interface Dialer1
description connected to Internet
ip address x.x.x.x 255.255.255.192
ip accounting output-packets
encapsulation ppp
no ip split-horizon
dialer pool 2
dialer idle-timeout 600
dialer enable-timeout 120
dialer string xxxxxxx
dialer hold-queue 10
no cdp enable
ppp authentication chap pap callin
ppp chap hostname ********
ppp chap password ********
ppp pap sent-username ********
ppp multilink
multilink load-threshold 1 either
!
ip classless
ip route 0.0.0.0 0.0.0.0 Dialer0
ip route 0.0.0.0 0.0.0.0 Dialer1 10
dialer-list 1 protocol ip permit
06-12-2003 04:38 AM
You have given back up interface as dialer interface under the atm interface.
This should be bri 0. Coz, this is the D channel which is responsible for call set up and call tear down and call maintainance.
Also specify the ppp multilink under the bri 0 interface.
-Deepau
06-12-2003 08:12 AM
The config scheme is fine.. You can use backup interface to dialer 1 as dialer 1 is linked with the bri interface using "dialer pool .." command. Its basically a dialer profile config.
Now once the atm interface will go down, you will see the dialer 1 interface comeout of "standby" mode and become "up/up spoofing" After that the interesting traffic should be able to trigger the dialout using dialer 1 interface.
But looking on the config under the interface dialer 1, command "dialer-group 1" is missing. You also need to add the remote-name presented by isp using "dialer remote-name xyz" where xyz is the name presented by isp side during authentication. Add "ppp authentication chap callin" under the bri interface too so the the call will be binded to dialer 1 during authentication.
Also you need to remove "ip route 0.0.0.0 0.0.0.0 Dialer0" as dialer 0 is not used anyway for dialout.
So once you add that, the backup should work fine.
Here is the link which discuss the isdn backup using backup interface command and using dialer profile
08-17-2003 09:58 PM
Hi,
I think the configuration is almost correcr. I faced the same problem here also. I noticed that when the atm interface 0 is down, but the dialer 0 is still active and spfooping, that why the floating static route can not kickon and the isdn can not dial. any idea how to make the dialer0 become down ,down when the atm 0 is down
07-08-2004 09:20 AM
I suspect Dialer1 needs the dialer-group 1 command in order for interesting traffic to dial the destination.
See second disadvantage of Backup Interfaces in http://www.cisco.com/warp/public/123/backup-main.html
07-08-2004 01:08 PM
Hate to burst your bubble, but even if you get this configuration to work, it won't help much because the approach is fundamentally flawed. Most of the time that DSL goes down, the interface stays up and backup interface will never kick in.
You need to use "ping based routing" to detect link down and establish the replacement default route. You can then use dial on demand for the dial backup. If you have a cco login, go to www.cisco.com/en/US/customer/products/sw/iosswrel/ps5413/products_feature_guide09186a00801d862d.html
(replace "customer" in the URL with "partner" if that is your kind of login). If you don't have a login, try searching on ping based routing or object tracking. Note that this feature requires IOS 12.3(8)T at a minimum.
Good luck and have fun!
Vincent C Jones
07-09-2004 07:10 AM
Good one, vcjones. I was wondering if "Reliable static routing backup using object tracking" works with PPPoA. The document only mentions its use for PPPoE and IPSec VPN.
07-09-2004 07:11 AM
Good one, vcjones. I was wondering if "Reliable static routing backup using object tracking" works with PPPoA. The document only mentions its use for PPPoE and IPSec VPN.
07-16-2004 02:32 AM
Did you get your configuration with "backup routing using object tracking" working.
I´m trying to do the same with a 836 but having problems with it.
As soon as I configure it like it is described in this document, the tracked route will never come up.
07-16-2004 11:58 AM
Unfortunately, I have not configured it yet as I have some other problem preventing me from configuring it.
When you say the tracked route, I suppose you mean the primary route. Are you saying that the backup route is constantly up?
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