Hi all:
We have ADSL service and have some weird problems. Some of our customers PPPoE/VPDN sessions would stay connected with NAS(LNS) routers for hours even they are idle:
Interface User Mode Idle Peer Address
Vi189 johndo1@company. PPPoVPDN 1d4h:02:05 xxx.xxx.xxx.xxx
Vi191 johndo2@company. PPPoVPDN 1d1h:01:11 xxx.xxx.xxx.xxx
Vi193 johndo3@company. PPPoVPDN 23:02:33 xxx.xxx.xxx.xxx
Vi195 johndo4@company. PPPoVPDN 18:02:14 xxx.xxx.xxx.xxx
The real problem is that those customers will call in and complain that they can’t connect to Internet. We have to clear those virtual interfaces up by command “clear interface virtual-access #” all the time. Now we are creating a script doing this. But it won’t resolve the actual problem.
Seem to me, this magnitude of the problem relates the configuration command “virtual-template 1 pre-clone xxx”; the larger the # “xxx” is, the severer the problem is. When I drop the number down to 50, fewer customers complain. But the routers’ CPU utilization starts getting higher than normal (one of router’s CPU actually reached 91% when over 2000 customers terminated on that router).
I also noticed that the most of those customers with such problem configure their home ADSL modems with so-called “nailed-in connection” instead of automatically timeout after a certain idle time. Personally I like this option since it seems to refresh the PPP sessions but would not destroy the VPDN tunnels; unfortunately, most of those customers don’t like this idea.
Could anyone here explains on this issue in details or help me find some information (such as white papers, URLs. I am very interested in the theory behind this)? The most important thing question is: how could I fix this from my site?
Thanks
