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Community Member

ISDN links and "dialer persistent"

I am trying to use the "dialer persistent" option on a Cisco 802 with IOS 12.2.8T5 to keep an ISDN link up all the time yet the router redials very frequently (over 100 calls per day). This is a problem since the local CLEC charges ISDN calls on a per call basis (not per minute). Would appreciate any suggestions. Dialer configuration is similar to the one listed belows (dialer string, username, password changed).



interface Dialer1

description myisp

ip unnumbered Loopback0

no ip proxy-arp

ip nat outside

encapsulation ppp

no ip split-horizon

dialer pool 1

dialer remote-name myisp

dialer idle-timeout 0

dialer string 8005551212

dialer hold-queue 10

dialer load-threshold 3 either

dialer persistent delay 15

dialer persistent max-attempts 8

dialer-group 1

ppp authentication pap callin

ppp pap sent-username password mypassword

ppp multilink


Re: ISDN links and "dialer persistent"


Dialer persistent, should not make the link down, unless a shutdown is given under the dialer interface. So, what I would suggest is to get back with following results.

1. Are you able to sent packets across the link when the link is up ??

2. How frequent are the calls being dialed ??

3. DUring offpeak hours, can you issue a debug isdn q931, so that we can understand if there is any issue at layer 3 signalling.

4. ALso try to give a debug ppp negotiation and get back to us with the results.

5. Please specify your IOS that you are using.

Community Member

Re: ISDN links and "dialer persistent"

Thanks for your suggestions. I will be doing some debugs later today.

It is a 128K ISDN link (2 channels) and over 100 calls per day are generated. Some calls last several hours and some last 15 to 20 minutes.

The IOS is 12.2.8T5 .

Is "ppp multilink" compatible with "dialer persistent" ? When multilink is enabled a "sho dialer in d1" shows "Dial reason: Multilink bundle overloaded" instead of "Dial reason: Persistent Dialer Profile".

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