[c-nsp] Problem mith MLPPPoE after provider switches from J to C ...

[Garry]

OK, here's the background ...

We have multiple customers set up to use multilink PPP on *DSL lines.
The DSL lines themselves come from German Telekom, which forwards
connections via L2TP to another provider, which in turn forwards them to
us, again via L2TP. Our LAC does IP provisioning, including IP
addresses, VRF etc.

On two sites that had been using a multilink connection with 2 and 3
SDSL lines for over a year, multilink stopped working when Telecom did
some announced maintenance work. Going back to just a single line
(doesn't matter which of the 2/3 lines, as long as it's only one) works
fine, though of course losing the bandwidth isn't an option.

Now, after investigating (and kicking their @** for messing around) I
was told yesterday that during the maintenance window, the customer
lines for both sites had been switched over from a Juniper box to Cisco.

Our setup is probably as basic as it gets, LAC looks something like this:

vpdn-group 1
 description Template fuer T-DSL-Sessions
 accept-dialin
  protocol l2tp
  virtual-template 1
 terminate-from hostname dslhandover
 lcp renegotiation always
 l2tp tunnel password xxx
 l2tp tunnel timeout no-session 30

interface Virtual-Template1
 description Template fuer T-DSL-Sessions
 mtu 1492
 ip unnumbered FastEthernet0/0.99
 ip route-cache flow
 ip tcp adjust-mss 1416
 peer default ip address pool dsl-pool
 keepalive 60
 down-when-looped
 ppp authentication chap pap callin
 ppp multilink

Customer side is pretty much standard, too ...

interface Dialer1
 ip address negotiated
 ip mtu 1492
 ip load-sharing per-packet
 encapsulation ppp
 no ip mroute-cache
 dialer pool 1
 dialer string dsl
 dialer-group 1
 keepalive 30
 ppp authentication chap callin
 ppp chap hostname xxx
 ppp chap password xxx
 ppp multilink

I'm kinda puzzled what could be causing this problem. The connection
still comes up fine as Multilink-bundle on both sides. One thing I have
noticed though is that one router (2600 w/ c2600-j1s3-mz.123-12a) sets
up the connection, and when doing more than one line, spits out this
error shortly after activating the second line:

1y50w: %SYS-2-INPUT_GETBUF: Bad getbuffer, bytes= 65535, for interface=
Virtual-Access4
-Process= "PPP Events", ipl= 3, pid= 105
-Traceback= 8033BBAC 80433838 8028134C 80281884 80281DC0 806A9594
806A2850 803BB370 806A27FC 8066E3B8 8068FC0C 8068FDA0 8066E914 803BD59C
803C0C48

Has anybody had something like this before, and could give me a hint as
to what could be causing this problem? If it can't be solved, I can have
the customer lines moved back to the Juniper system, though I would
prefer to find a solution that would also work for sites that do not
have a J system available ...

Tnx, -gg