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PPP Multilink problems with both isdn b channel up

I've experienced these problems everytime I enable dual b channel of the ISDN to connect to the Internet.

The commands that I used are

interface bri0

dialer load-threshold 1 either -> because I want both channel to be up all the time

ppp multilink

With both channel up I found the following problems :

1. If I send large attachment with outlook express it will be stopped halfway

2. Lotus notes behind my router failed to replicate its database to the other lotus notes server in the internet.

3. Microsoft terminal services server some time have problem to be accessed if the client is behind my router.

I've already tested using other cisco router with the same result, but the above problems will be solved if I drop one b channel. Strange thing is if I tried using ISDN modem or other ISDN router with both channel up there won't be any problem.

Community Member

Re: PPP Multilink problems with both isdn b channel up

hi, I don't know whether this is the solution for your problem, but try

dialer load-thres 25 either

because we had often problems with isdn connections when we used 1 instead of 25. It don't have to be 25, but we used it in our configs.

Community Member

Re: PPP Multilink problems with both isdn b channel up

Have you tried using debug dialer to give you hints as to where the process is failing? When both b channels are active, do you see them both up or are they droping after a set amount of time with out sending anything accross except for a seady ping. Can you ping accoss fine after both chanels are up? debug q931 will tell you if layer 3 traffic is transmiting properly. Also, before you try sending an outlook attached file, clear out the counters in the router and then when it fails, show multilink ppp. It will tell you errors for each BRI. As for your last sentence, what's the deal with your router? When you swap them out, the process works fine?

I'm not an expert, but these are the things I would verify first.

Community Member

Re: PPP Multilink problems with both isdn b channel up

Hi, thanks for your answer. I've already tried to debug with the q931 but so far I don't see any channels dropped or acting funny, but other activities such as browsing, FTP and downloading, I can do them just fine with both b channels up. the problems looks to be application specific, but as I said when i tried to swap the router and use a diva lan modem, it works just fine with the two channel up, and then I also tried using a cheap eicon router, its suprisingly works perfectly

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