2 Dialer Profiles for 1 ATM Interface (836)

[MaseBarnes]

Hi,

I'm managing many Homeoffices connected wit h a 836 without any problems. My local provider sometimes has problems with their realms in userid's, so I thought I could create a second dialer interface configured with a different (e.g. call by call) account.

But everytime I do this, the 836 only connects to the last dialer interface. When I set it to shut it never dials the first one. Also changing the accounts from 0 to 1 lets me only dial the second dialer. I've tested it on 12.3T and 12.4T. With, and without CEF and most dialer-watch examples, Everything doensn't work.

Here's a sample config:

interface ATM0

bandwidth 160

no ip address

no atm ilmi-keepalive

atm ilmi-pvc-discovery

dsl operating-mode annexb-ur2

pvc 1/32

pppoe-client dial-pool-number 1

!

!

[...]

interface Dialer0

ip address negotiated

ip mtu 1492

ip nat outside

ip virtual-reassembly

encapsulation ppp

ip tcp adjust-mss 1300

dialer pool 1

dialer-group 1

no cdp enable

ppp authentication pap callin

ppp pap sent-username XXX@XXX.de password xxxx

ppp ipcp dns request

ppp ipcp wins request

!

interface Dialer1

ip address negotiated

ip mtu 1492

ip nat outside

ip virtual-reassembly

encapsulation ppp

ip tcp adjust-mss 1300

dialer pool 1

dialer-group 1

no cdp enable

ppp authentication pap callin

ppp pap sent-username ZZZ@ZZZ.de password xxxx

ppp ipcp dns request

ppp ipcp wins request

!

[...]

dialer-list 1 protocol ip permit

Is there something I forgot? Thanks

Mase

[lgijssel]

It would be nice to know how you arranged ip routing for this setup. The router chooses the outgoing interface primarily based on the routing table.

if you had something like: ip route 0.0.0.0 0.0.0.0 interface dialer 1, I would consider it logical for the router to behave as described.

Regards,

Leo

[MaseBarnes]

Hi Leo,

thanks for you answer! I've set 0.0.0.0 to dialer 1 with metric 10 and 0.0.0.0 to dialer 0 with metric 20. My thought was that Cisco will router to dialer 0 automatically when dialer 1 changed to down. Disabling the metric will result in a packetloss of 50% because the Cisco wants to send the packets over both lines.

Is there another way to solve the routing issue?

Thanks!

[lgijssel]

The dialer is software-constructed interface that is always in a state of up-spoofed. The router simply used the route with the best metric.

I am afraid that the issue cannot be solved using static routes as they will never be able to reflect the actual availability of the ISP.

You should make the switch-over by hand.

Regards,

Leo

[MaseBarnes]

Isn't there another way, like replacing Dialer If's with VirtualTemplates? So I also can't use dialer-watch with 2 Dialer If's?

Thanks,

Mase

[lgijssel]

I am afraid there will be little other options.

You probably shouldn't bother too much as all existing connections will die anyway when there is a switchover to another dialer. This is because the existing nat translations will be invalid on the other dialer. This also implies that you will be reconnecting using a different IP which is equivalent to a new session when seen from the connected Internethost.

Regards,

Leo

[MaseBarnes]

I don't want to use it for 24h disconnects. My first DialUp provider sometimes has problems with his infrastructure and the connections is down for about half an hour. So I want to keep the downtime as short as possible and connect to another one. It's ok if the clients lose their connections for a short time, but I can't dial in (over ISDN) to all customers and activate the second dialer connection.

Thanks,

Mase

[aroshak]

Hay Guys,

I know this post is quite old. but I thought i might share this because it could potentially help someone else who has the same problem.

I think if you configure "ppp ipcp route default" under the main dialer it will inject a default route to the global table. when dialer is offline it will remove it. Then you can have a static default route with a higher admin distance and it will kick in.

hope this will be helpful.

Cheers