L2TP configuration command directory
Showing the channel of 12tp and statistic information of sessions.
show l2tp [tunnel | session]
parameter:
tunnel Showing
statistic information of channel
session Showing
statistic information of sessions ¡¡
Command mode:
Non-user mode¡¡
Explanation:
Showing the existing channel and the related statistic information of the sessions.
Example:
37DE#show l2tp tunnel
L2TP Tunnel Information Total tunnels 1 sessions 1
LocID RemID Remote Name State Remote Address Port Sessions
2 27204 cisco26 Est 192.168.20.156 1701 1
The first line is the number of the tunnels and the sessions.
Area |
Description |
LocID |
Local ID of the channel |
RemID |
Remote ID of the channel |
Remote Name |
Name of remote channel of the channel |
State |
Current channel status |
Remote Address |
Remote IP address of the channel |
Port |
Remote port number of the channel |
sessions |
The number of the session contained in
the channel. |
At the time of clearing the tunnel, the tunnel of the designated tunnel ID is cleared (all the sessions under the tunnel will also be cleared.). At the time of clearing session, the session of the designated session ID under the tunnel of the designated tunnel ID is cleared.
clear l2tp [tunnel tunnelID tunnelID-number | session
tunnelID tunnelID-number sessionID sessionID-number]
parameter:
tunnel Clearing the channel
session Clearing the session
¡¡
Command mode:
Supervisor mode
Explanation:
Clearing the channel of the designated tunnel ID or clearing the session of the designated session ID under the designated tunnel ID channel. The numeric area of tunnel ID and session ID is <1-65535>.¡¡
Example:
Observing the existed channel and session before clearing (including a channel and a session)
37DE#show l2tp tunnel
L2TP Tunnel Information Total tunnels 1 sessions 1
LocID RemID Remote Name State Remote Address Port Sessions
2 14914 cisco26 Est 192.168.20.156 1701 1
37DE#show l2tp session
L2TP Session Information Total tunnels 1 sessions 1
LocID RemID TunnelID Intf Username State
1 3391 2 vn1 (null) Est
Clearing session 1 in channel 2.
37DE#clear l2tp session tunnelID 2 sessionID 1
Observing the remaining channel and session after clearing. The session has been cleared and the channels still exists.
37DE#show l2tp tunnel
L2TP Tunnel Information Total tunnels 1 sessions 0
LocID RemID Remote Name State Remote Address Port Sessions
2 14914 cisco26 Est 192.168.20.156 1701 0
37DE#show l2tp session
L2TP Session Information Total tunnels 1 sessions 0
The abnormal operation of the module or error occurrence at the time of printing or the erroneous information; printing the event information when the module operation triggers the event, printing the content of the data packet received or sent by the module.
(no) debug l2tp [error | event | packets [control-packets |
data-packets | detail]]
The command ¡°no debug l2tp¡± is used for stopping the display of information
parameter:
Error |
Showing the abnormity of l2tp module operation |
Event |
Showing event triggering information of
l2tp
module. |
Packets |
Showing the content of the data packet received
and sent by l2tp
module (including control packet and data packet. |
Sub-command parameter of packets:
control-packets |
Showing the content of the control
packet received and sent by L2TP module. |
data_packets |
Showing the content of the data packet received
and sent by L2TP module. |
Detail |
Opening the switch of printing the
detailed content of the packet received by the module. |
Note: Executing the command:
debug l2tp packets
equaling to execute the two commands
below:
debug l2tp packets
control-packets
debug l2tp packets
data-packets
Executing the command:
no debug l2tp packets
Equaling to execute the two commands below:
no debug l2tp packets control-packets
no debug l2tp packets data-packets
The command ¡°debug l2tp packets detail¡± is only a switch. Opening the ¡°debug¡± along is not able to print the content of the data packet. If the command ¡°debug l2tp packets control-packets¡± is configured simultaneously, the detailed information of the control packet will be printed. Similarly, if the command ¡°debug l2tp packets data-packets¡± is configured simultaneously, the detailed information of the data packet will be printed. If the ¡°debug¡± is not configured, only the summary information of debug control packet and data packet will be printed.
¡¡
Command mode:
Supervisor mode
¡¡
Explanation:
After l2tp debug information is opened, the erroneous information of l2tp module, event triggering information and the content of the data packet received and sent can be exported to help the user diagnose l2tp trouble.¡¡
Example:
Configuration Command:
37DE#debug l2tp packets control-packets
37DE#debug l2tp packets detail
Print Information:
2003-1-14 11:19:23
L2TP TX -> ctrl packet: flg TLS,ver 2,len 55,TunlID 0,SesnID 0,Ns 0,Nr 0 :SCCRQ
2003-1-14 11:19:23
L2TP Control Packet Header :
C8 02 00 37 00 00 00 00 00 00 00 00 ...7........
2003-1-14 11:19:23
L2TP avp Message Type :
80 08 00 00 00 00 00 01 ........
2003-1-14 11:19:24
L2TP avp Protocol Version :
80 08 00 00 00 02 01 00 ........
2003-1-14 11:19:24
L2TP avp Framing Capabilities :
80 0A 00 00 00 03 00 00 00 00 ..........
2003-1-14 11:19:24
L2TP avp Assigned Tunnel ID :
80 08 00 00 00 09 00 02 ........
2003-1-14 11:19:24
L2TP avp Host name :
80 09 00 00 00 07 6C 61 63 ......lac
When the module receives SCCRQ control packet, it divides the packet into L2TP header and some AVPs and shows the specific content of each AVP. (If the command ¡°debug l2tp packets detail¡± is not configured, the content of the packet will not be divided).
Area |
Description |
L2TP |
Name of protocol |
TX -> |
Direction of packet transmission (it
means outward transmission here) . |
ctrl packet |
Packet type (It is classified into control
packet and data packet) |
flg |
The flags contained in L2TP header. |
ver |
Protocol version of L2T pprotocol |
len |
Length of the whole packet |
TunlID |
The channel ID number contained in L2TP
header. |
SesnID |
The session ID number contained in L2TP
header. |
Ns |
Sequence number of
sending the channel |
Nr |
Sequence number of
receiving the channel |
SCCRQ |
Type of the control
packet |
L2TP Control Packet Header: |
Content of L2TP
header of the control packet. |
L2TP avp |
AVP contained in
the control packet (AVP type and content followed) |
The following is the event information of l2tp negotiation process.
37DE#debug l2tp event
2003-1-14 10:58:51 L2TP: Tunl 6 be created.
2003-1-14 10:58:51 Tunl 6 L2TP: status changed into IDLE
2003-1-14 10:58:51 Tunl 6 L2TP: Sesn 1 be created.
2003-1-14 10:58:51 Tunl/Sesn 6/1 L2TP: status changed into IDLE
2003-1-14 10:58:51 Tunl 6 L2TP: TX -> SCCRQ to Tunl 0
2003-1-14 10:58:51 Tunl 6 L2TP: status changed into WAIT REPLY
2003-1-14 10:58:51 Tunl 6 L2TP: RX <- SCCRP from cisco26 Tunl 12871
2003-1-14 10:58:51 Tunl 6 L2TP: TX -> SCCCN to cisco26 Tunl 12871
2003-1-14 10:58:51 Tunl 6 L2TP: status changed into ESTABLISHED
2003-1-14 10:58:51 Tunl/Sesn 6/1 L2TP: TX -> ICRQ to cisco26 Tunl/Sesn 12871/0
2003-1-14 10:58:51 Tunl/Sesn 6/1 L2TP: status changed into WAIT REPLY
2003-1-14 10:58:51 Tunl 6 L2TP: RX <- ZLB from cisco26 Tunl 12871
2003-1-14 10:58:51 Tunl/Sesn 6/1 L2TP: RX <- ICRP from cisco26 Tunl/Sesn 12871/3387
2003-1-14 10:58:51 Tunl/Sesn 6/1 L2TP: TX -> ICCN to cisco26 Tunl/Sesn 12871/3387
2003-1-14 10:58:51 Tunl/Sesn 6/1 L2TP: status changed into ESTABLISHED
2003-1-14 10:58:51 Line on Interface Virtual-tunnel1, changed state to up
2003-1-14 10:58:51 Tunl 6 L2TP: RX <- ZLB from cisco26 Tunl 12871
Area |
Description |
Tunl/Sesn |
Local channel and ID number of the
session (if the control packet of the channel is sent, there will be only an
ID number of the channel. The same below.). |
L2TP |
Name of protocol |
TX -> |
Direction of packet transmission (it
means outward transmission here) . |
ICCN |
Type of control
packet |
Cisco26 |
Name of remote
channel |
Tunl/Sesn |
Remote channel and
ID number of the session. |
¡¡