show tcp syn-cookies

Last Updated : Nov 06, 2012 |

Displays SYN cookies statistics for inbound TCP connections.

Note:

This command applies to IPv4 only.

Syntax

show tcp syn-cookies

User level

read-only

Context

general

Example

To show SYN cookies statistics:

Gxxx-001(super)# show tcp syn-cookies
Status: Enabled
Statistics:
SYN rcvd                              10
Connections established                9
local address          remote address        state           Last access (sec)
---------------------  --------------------  --------------  ----------------
192.113.241.201:60342  111.211.131.1:80      IN_PROGRESS             1
192.113.241.201:23     221.2.11.11:432       ESTABLISHED          1200
192.113.241.201:23     121.192.171.121:7311  CLOSING                10

Output fields

Field

Description

Status

The operational status of the TCP SYN cookies defense mechanism: Enabled or Disabled

SYN rcvd

The total number of TCP SYN packets received since the last time the counters were reset

Connections established

The total number of connections that were established since the last time the counters were reset

local address

The local IP address and port of the connection

remote address

The remote IP address and port of the connection

state

The state of the connection:

  • IN_PROGRESS — connection is in progress

  • ESTABLISHED — connection is established

  • CLOSING — connection is closing

Last access

The seconds elapsed since the last time a packet was received on the connection from either side