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New Member

ISDN -cisco 804

I Have two 804 connected with ISDN

it work fine but only one chanel is up (64k)

even though all my sh isdn status or

sh running config are fine.

I am in Canada we use ni.

telephone company say that my spid are the right one

Neither of the router pick up the second chanel

(phone number)call.

I try to call both of those number with a standard telephone it ring without answering.

My telephone company say everithing is fine

and the problem comes from cisco 804.

Many IT professional confirm me that there is no

real problem to connect a 804 to ISDN.

anyone can help me.


New Member

Re: ISDN -cisco 804

Do you have the following commands in your config?

>ppp multilink

>dialer load-threshold load [outbound | inbound | either]

check out this page on CCO:


Kemraj Sewnarain (Snr.Network Eng)

Tenacent, Burlingame CA

New Member

Re: ISDN -cisco 804

I don't know about the part where the router doesn't pick up the call from a telephone. Can't recall ever having tried that.

It is difficult to know for sure what your issues are, but I think that maybe if you set a threshold on your BRI, it will bring up the second b channel when exceeded.

Router(conf-if)# dialer load-threshold {0-255} {outbound | inbound | either}

I also think that you need ppp multilink enabled

Router(conf-if)#ppp multilink

If that isn’t the problem, maybe this link can help:

New Member

Re: ISDN -cisco 804

Thank you for your help,


Yes ppp multilink is enable

and dialer load-threshold 30 either

like I said, all my parametre are fine

and all test and show command pretend that

everithing works fine.

In those condition, hard to put the finger on it!!!

(cisco tac employee told me)

The problem seem to be the telephone company

as he said.

but them pretend that it's cisco that have a

problem with that router version!!!!


see where my frustration come from!!!

PS: sorry for the poor English, I'm a French Candian


New Member

Re: ISDN -cisco 804

we recentloy ran into a similar problem and it turned out to be telco. same finger pointing quagmire.

we kept escalating till it miraculously it worked unfortnately they said they "did not do anything". funny thing is our config never changed.

Yeaah !!! right must have been gremlins

New Member

Re: ISDN -cisco 804


I don't know about Cisco 804, but I have tried this on normal routers with bri port (2600 and 3600 series ).

In the calling router, go to "conf t" "bri x/y" say, "dialer load-threshold 1 either" this forces the router to bring up the second channel immediatly.

( the digit 1(no load) indicates at what load to bring up the second channel, it can be any vlaue from 1-255)

Let me know if it works :- )

New Member

Re: ISDN -cisco 804


thank you but I did try that already

since my threshold was

at 30 so I put it at 1 and unfortunatelly

it didn't change my problem...


New Member

Re: ISDN -cisco 804

Just confirming: We have the exact same problem! We are trying to replace our Ascend routers with Cisco 2621 routers. We were able moved our 2621 on the receiving end to another site/building with a different ISDN circuit to test it there. It worked just fine, both channels picked up, at the test site and worked they way we expected. We are now trying to convince a reluctant telco to dig further into the problem at our original site.

New Member

Re: ISDN -cisco 804

Even though our telco claims that the line is provisioned for rollover, we were never able to successfully bring up the second channel using only one dialer string; debug would always show the line busy. When using two dialer strings, router would call the second string before the switch was apparently able to handle it. We saw this indication when we added a third dialer string and it worked consistently on the third call. The Cisco tech recommended we configure router with "isdn fast-rollover-delay 5". With this command in the dialer interface and using only the two original dialer strings, both channels came up as expected.

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