Manual

Layer 2 Tunnel Protocol Version 3
debug vpdn
85
Cisco IOS Releases 12.0(29)S and 12.2(25)S
debug vpdn
To troubleshoot Layer 2 Tunnel Protocol Version 3 (L2TPv3) and the surrounding Layer 2 tunneling
infrastructure, use the debug vpdn command in privileged EXEC mode. To disable the debug vpdn
command, use the no form of this command.
debug vpdn {error | event | l2x-errors | l2x-events | l2x-packets | packet | packet detail | packet
errors}
no debug vpdn {error | event | l2x-errors | l2x-events | l2x-packets | packet | packet detail |
packet errors}
Syntax Description
Command Modes Privileged EXEC
Command History
Usage Guidelines Note that the debug vpdn packet and debug vpdn packet detail commands generate several debug
operations per packet. Depending on the L2TP traffic pattern, these commands may cause the CPU load
to increase to a high level that impacts performance.
Examples The following example shows output from the debug vpdn command for an Xconnect session on an
Ethernet interface. The output is self-explanatory.
Router# debug vpdn
23:31:18: L2X: l2tun session [1669204400], event [client request], old state [open], new
state [open]
23:31:18: L2X: L2TP: Received L2TUN message <Connect>
23:31:18: Tnl/Sn58458/28568 L2TP: Session state change from idle to wait-for-tunnel
23:31:18: Tnl/Sn58458/28568 L2TP: Create session
23:31:18: Tnl58458 L2TP: SM State idle
23:31:18: Tnl58458 L2TP: O SCCRQ
23:31:18: Tnl58458 L2TP: Control channel retransmit delay set to 1 seconds
error Displays errors that occur in protocol-independent conditions.
event Displays events resulting from protocol-independent conditions.
l2x-errors Displays errors that occur in protocol-specific conditions.
l2x-events Displays events resulting from protocol-specific conditions.
l2x-packets Displays detailed information about control packets in protocol-specific
conditions.
packet Displays information about high-level Layer 2 control packets.
packet detail Displays detailed packet information, including packet dumps.
packet errors Displays errors that occur in packet processing.
Release Modification
12.0(23)S This command was introduced.
12.2(25)S This command was integrated into Cisco IOS Release 12.2(25)S.