[nsp] Connecting Max6000 with Cisco 2500 over HDSL: "lineprotocolis down"

[Tim Franklin]

cisco-nsp-bounces at puck.nether.net wrote:

> "no ip adress" will actually disable IP processing (including
> PPP/IPCP) on that interface - you need "ip unnumbered <something>" or
> an explicit IP address.  Otherwise the interface will happily do CDP,
> IPX, IPv6, ... (whatever is available and configured) but *not* IP.
>
> This is *not* related to the interface being "up/down", though -
> without IP address, but everything else being correct, the interface
> will come up to "up/up" state, but then ignore all routing info
> configured to it ("ip route ... serial0" will be visible in the
> config, but not have any effect) and not pass IP packets.

What's on the other end may have some effect on this.  I've had fun with
bringing up a PPP connection between a "less than excellent" router
*cough*BATM*cough* and a Cisco 7609, where the BATM (in the config used)
insists on IPCP completing, otherwise it tears down the whole PPP session.
Cisco with "no ip address" on the interface won't run IPCP (LCP starts
fine), so the whole thing sits "up/down" forever.

(A nice loop in this case, as I was relying on a provisioning tool to put
the address on the interface, and the tool won't configure an interface
until it's up/up.  You wait... time passes...)

I don't know if the Ascend is similarly picky, but it's a possibility.

Regards,
Tim.

--
____________   Tim Franklin                 e: tim at colt.net
\C/\O/\L/\T/   Product Engineering Manager  w: www.colt.net
 V  V  V  V    Managed Data Services        t: +44 20 7863 5714
                                            f: +44 20 7863 5876