Troubleshooting PPP Interfaces

Problem

Description: To analyze and diagnose issues with the PPP interface, you must have access to detailed information on the most recent PPP operations. By default, nothing is traced.

Solution

For static PPP interfaces, you can configure a packet trace log for a PPP interface to diagnose issues on the PPP interface. First, specify a PPP interface which can be any one of the following interface types:

Note: For more information, see Interface Types and Specifiers in JunosE Command Reference Guide.

host1(config-if)#log severity debug pppPacket serial 0/0:1/1 DEBUG 01/01/1970 00:16:58 pppPacket (1000001,*): interface:0/0:1/11/0:1,time: 0.00, tx lcp confReq, id = 226, length = 19, mru = 32759,authentication = chap MD5,magicNumber = 0x5387f9a2
DEBUG 01/01/1970 00:16:58 pppPacket (1000001,*): interface: 0/0:1/11/0:1,time: 0.01, rx lcp confReq, id = 156, length = 18, mru = 32759,magicNumber = 0x2d8eac91, pfc, acfc
DEBUG 01/01/1970 00:16:58 pppPacket (1000001,*): interface: 0/0:1/11/0:1,time: 0.01, tx lcp confAck, id = 156, length = 18, mru = 32759, magicNumber = 0x2d8eac91, pfc, acfc

You can also configure logging to direct the output to a specific destination. For information, see Overview of System Logging.

On dynamic PPP interfaces, you can use the ppp log command within the profile, as described in Configuring MLPPP and PPP Characteristics for a Profile. To enable PPP packet or state machine logging on any dynamic interface that uses the profile being configured, use one of the following keywords:

host1(config-profile)#ppp log pppPacket

Note: This command is equivalent to the log severity debug pppPacket and log severity debug pppStateMachine commands.

Related Documentation