Cleared OUT

If the LAPD is not alive, the reason could be one of the following:

1.The TEI mode has been set incorrectly.

On a Basic Rate interface, the TEI mode ought to be automatic, so that the router does not mandate a TEI value to the switch, but will automatically accept whatever value is assigned by the switch. The TEI mode of the BRI interface is shown in the first line of output from the show lapd command. If the value shown in the TEI Mode column is automatic, then the interface has been set properly. If the value is shown as non-automatic, then the interface has not been set up properly. Use the command:

set lapd=n mode=automatic

Note: It may be necessary to set this in the router's config script, and reboot the router.

2.There is a problem in the ISDN network.

If the router is sending valid LAPD packets, and the switch is not responding correctly, then LAPD will stay in the DEAD state. Contact your ISDN network provider and report a network fault.

Step 3: Are ISDN calls connecting successfully?

If the router has an LAPD connection to the switch, then when an outgoing call is made from the router, it will send call setup messages to the switch. If the switch believes that the packet is valid and there are channels available in the ISDN network, it will forward it on to the router at the far end of the link. The receiving router will then either accept or reject the call, depending on the contents of the packet.

If the receiving router accepts the call setup request, the ISDN call will come open, and the routers will endeavour to exchange data packets. If the call does not come open, then there will obviously be no exchange of data. In order to determine whether calls are coming open, use the command:

show isdn log

which will output a record of the last few ISDN calls, successful or otherwise, as shown in the following figure.

Call Name Start TimeDuration Dir Number Cause

-----------------------------------------------------------------------------

tdc	12-Dec-1997 11:18:51		CLEARED OUT 035439003	U16,-
chs	12-Dec-1997 11:19:03		CLEARED OUT 073333333	N1,-
ajpwlg	12-Dec-1997 11:19:36		0:01:01 OUT 044940190	U16,-
ajpwlg	12-Dec-1997 11:23:12		0:01:01 OUT 044940190	U16,-
abb	12-Dec-1997 11:23:33		0:00:49 OUT 093560114	U16,-
ajpwlg	12-Dec-1997 11:24:05		CLEARED OUT	-
ajpwlg	12-Dec-1997 11:24:25		0:01:02 OUT 044940190	U16,-
ajpwlg	12-Dec-1997 11:24:27		CLEARED OUT 044940190	N21,-
gc	12-Dec-1997	11:25:14	CLEARED OUT 3776569	N27,-
ppta	12-Dec-1997	11:25:38	CLEARED OUT 043842672	N17,-
to_boe	12-Dec-1997	11:26:13	CLEARED OUT 00441256376991	N18,-
pfricc	12-Dec-1997	11:26:38	CLEARED OUT 3432977	N17,-

-----------------------------------------------------------------------------

No ISDN logging port defined.

Step 3: Are ISDN calls connecting successfully?