Troubleshooting The Frame Relay Interface - HP ProCurve 7000dl Series Basic Management And Configuration Manual

Configuring the Data Link Layer Protocol for E1, T1, and Serial Interfaces
Troubleshooting Logical Interfaces
C a u t i o n
6-66
Incompatible Authentication Protocols. If you do not receive any PPP
authentication debug messages at all, the local and remote routers may be
requesting different authentication protocols. In this case, the LCP state will
not come up because the peers cannot negotiate the authentication option.
You could test this theory by debugging PPP negotiation events and looking
for a Conf-Nak message. This message indicates that one of the peer's must
refuse an option proposed by the other.
PPP debug messages are processor intensive: peers exchange LCP frames
again and again in an attempt to negotiate the session. If the router is currently
supporting network traffic, debugs can compromise its functions. When you
suspect that authentication is keeping a connection from going up, you can
simply try changing the type of authentication you require or send. If the PPP
connection then goes up (or if PPP authentication debug messages appear),
you know that incompatible authentication protocols were at least partially
at fault.
In Figure 6-27, the local router requires PAP, but the remote router is config-
ured for CHAP.
ProCurve# debug ppp negotiation
2005.07.08 09:11:12 PPP.NEGOTIATION PPPrx[t1 1/1] LCP: Conf-Req ID=74
Len=20 ACCM(00000000) AP(PAP)MAGIC(da5bf7de)
Peer requires PAP
2005.07.08 09:11:12 PPP.NEGOTIATION PPPtx[t1 1/1] LCP: Conf-Nak D=74
Len=9 AP(CHAP)
Figure 6-27. Debugs for Incompatible Authentication Protocols

Troubleshooting the Frame Relay Interface

When you troubleshoot the Frame Relay connection, you should first check
the Frame Relay interface and then check the Frame Relay subinterface. From
the enable mode context, enter the following command to check the status of
a Frame Relay interface that is bound to the E1, T1, or serial interface:
Syntax: show interface frame-relay <number>
Peer requests PAP, but the
local router requires CHAP
Message from the peer