Configuring Terminal Settings and Sessions

This chapter describes how to configure terminal settings and sessions.

Information About Terminal Settings and Sessions

This section includes information about terminal settings and sessions.

Terminal Session Settings

The Cisco NX-OS software features allow you to manage the following characteristics of terminals:

Terminal type
Name used by Telnet when communicating with remote hosts
Length
Number of lines of command output displayed before pausing
Width
Number of characters displayed before wrapping the line
Inactive session timeout
Number of minutes that a session remains inactive before the device terminates it

Console Port

The console port is an asynchronous serial port that allows you to connect to the device for initial configuration through a standard RS-232 port with an RJ-45 connector. Any device connected to this port must be capable of asynchronous transmission. You can configure the following parameters for the console port:

Data bits
Specifies the number of bits in an 8-bit byte that is used for data.
Inactive session timeout
Specifies the number of minutes a session can be inactive before it is terminated.
Parity
Specifies the odd or even parity for error detection.
Speed
Specifies the transmission speed for the connection.
Stop bits
Specifies the stop bits for an asynchronous line.

Configure your terminal emulator with 9600 baud, 8 data bits, 1 stop bit, and no parity.

COM1 Port

A COM1 port is an RS-232 port with a DB-9 interface that enables you to connect to an external serial communication device such as a modem. You can configure the following parameters for the COM1 port:

Data bits
Specifies the number of bits in an 8-bit byte that is used for data.
Hardware flowcontrol
Enables the flow-control hardware.
Parity
Specifies the odd or even parity for error detection.
Speed
Specifies the transmission speed for the connection.
Stop bits
Specifies the stop bits for an asynchronous line.

Configure your terminal emulator with 9600 baud, 8 data bits, 1 stop bit, and no parity.

Virtual Terminals

You can use virtual terminal lines to connect to your Cisco NX-OS device. Secure Shell (SSH) and Telnet create virtual terminal sessions. You can configure an inactive session timeout and a maximum sessions limit for virtual terminals.

Modem Support

You can connect a modem to the COM1 or console ports only on the supervisor 1 module. The following modems were tested on devices running the Cisco NX-OS software:


Note

Do not connect a modem when the device is booting. Only connect the modem when the device is powered up.

The Cisco NX-OS software has the default initialization string (ATE0Q1&D2&C1S0=1\015) to detect connected modems. The default string is defined as follows:

AT
Attention
E0 (required)
No echo
Q1
Result code on
&D2
Normal data terminal ready (DTR) option
&C1
Enable tracking the state of the data carrier
S0=1
Pick up after one ring
\015 (required)
Carriage return in octal

Configuring the Console Port

You can set the following characteristics for the console port:

  • Data bits

  • Inactive session timeout

  • Parity

  • Speed

  • Stop bits

Before you begin

Log in to the console port.

SUMMARY STEPS

  1. configure terminal
  2. line console
  3. databits bits
  4. exec-timeout minutes
  5. parity {even | none | odd }
  6. speed {300 | 1200 | 2400 | 4800 | 9600 | 38400 | 57600 | 115200 }
  7. stopbits {1 | 2 }
  8. exit
  9. (Optional) show line console
  10. (Optional) copy running-config startup-config

DETAILED STEPS

  Command or Action Purpose
Step 1

configure terminal

Example:

switch# configure terminal
switch(config)#

Enters global configuration mode.
Step 2

line console

Example:

switch# line console
switch(config-console)#

Enters console configuration mode.
Step 3

databits bits

Example:

switch(config-console)# databits 7

Configures the number of data bits per byte. The range is from 5 to 8. The default is 8.
Step 4

exec-timeout minutes

Example:

switch(config-console)# exec-timeout 30

Configures the timeout for an inactive session. The range is from 0 to 525600 minutes (8760 hours). A value of 0 minutes disables the session timeout. The default is 30 minutes.

Step 5

parity {even | none | odd }

Example:

switch(config-console)# parity even

Configures the parity. The default is none .

Step 6

speed {300 | 1200 | 2400 | 4800 | 9600 | 38400 | 57600 | 115200 }

Example:

switch(config-console)# speed 115200

Configures the transmit and receive speed. The default is 9600 .

Step 7

stopbits {1 | 2 }

Example:

switch(config-console)# stopbits 2

Configures the stop bits. The default is 1 .

Step 8

exit

Example:

switch(config-console)# exit
switch(config)#

Exits console configuration mode.
Step 9

(Optional) show line console

Example:

switch(config)# show line console
 (Optional)

Displays the console settings.
Step 10

(Optional) copy running-config startup-config

Example:

switch(config)# copy running-config startup-config
 (Optional)

Copies the running configuration to the startup configuration.

Configuring the COM1 Port

You can set the following characteristics for the COM1 port:

  • Data bits

  • Flow control on the hardware

  • Parity

  • Speed

  • Stop bits

Before you begin

Log in to the console port or COM1 port.

SUMMARY STEPS

  1. configure terminal
  2. line com1
  3. databits bits
  4. flowcontrol hardware
  5. parity {even | none | odd }
  6. speed {300 | 1200 | 2400 | 4800 | 9600 | 38400 | 57600 | 115200 }
  7. stopbits {1 | 2 }
  8. exit
  9. (Optional) show line com1
  10. (Optional) copy running-config startup-config

DETAILED STEPS

  Command or Action Purpose
Step 1

configure terminal

Example:

switch# configure terminal
switch(config)#

Enters global configuration mode.
Step 2

line com1

Example:

switch# line com1
switch(config-com1)#

Enters COM1 configuration mode.
Step 3

databits bits

Example:

switch(config-com1)# databits 7

Configures the number of data bits per byte. The range is from 5 to 8. The default is 8.
Step 4

flowcontrol hardware

Example:

switch(config-com1)# flowcontrol hardware

Enables flow control on the hardware. The default is enabled.

Use the no flowcontrol hardware command to disable flow control on the hardware.

Step 5

parity {even | none | odd }

Example:

switch(config-com1)# parity even

Configures the parity. The default is none .

Step 6

speed {300 | 1200 | 2400 | 4800 | 9600 | 38400 | 57600 | 115200 }

Example:

switch(config-com1)# speed 115200

Configures the transmit and receive speed. The default is 9600 .

Step 7

stopbits {1 | 2 }

Example:

switch(config-com1)# stopbits 2

Configures the stop bits. The default is 1 .

Step 8

exit

Example:

switch(config-com1)# exit
switch(config)#

Exits COM1 configuration mode.
Step 9

(Optional) show line com1

Example:

switch(config)# show line com1
 (Optional)

Displays the COM1 port settings.
Step 10

(Optional) copy running-config startup-config

Example:

switch(config)# copy running-config startup-config
 (Optional)

Copies the running configuration to the startup configuration.

Configuring Virtual Terminals

This section describes how to configure virtual terminals on Cisco NX-OS devices.

Configuring the Inactive Session Timeout

You can configure a timeout for inactive virtual terminal sessions on a Cisco NX-OS device.

SUMMARY STEPS

  1. configure terminal
  2. line vty
    • exec-timeout minutes
    • absolute-timeout minutes
  4. exit
  5. (Optional) show running-config all | begin vty
  6. (Optional) copy running-config startup-config

DETAILED STEPS

  Command or Action Purpose
Step 1

configure terminal

Example:

switch# configure terminal
switch(config)#

Enters global configuration mode.

Step 2

line vty

Example:

switch# line vty
switch(config-line)#

Enters line configuration mode.

Step 3

  • exec-timeout minutes
  • absolute-timeout minutes

Example:

switch(config-line)# exec-timeout 30

Example:

switch(config-line)# absolute-timeout 30

Configures the inactive session timeout. The range is from 0 to 525600 minutes (8760 hours). A value of 0 minutes disables the timeout. The default value is 30.

Sets a timeout interval on a virtual terminal (vty) line. The range is from 0 to 10000.

The absolute-timeout command terminates the connection after the specified time period has elapsed, regardless of whether the connection is being used at the time of termination. You can specify an absolute-timeout value for each port. The user is given 20 seconds notice before the session is terminated. You can use this command along with the logout-warning command, which notifies the user of an impending logout.

Step 4

exit

Example:

switch(config-line)# exit
switch(config)#

Exits line configuration mode.

Step 5

(Optional) show running-config all | begin vty

Example:

switch(config)# show running-config all | begin vty
 (Optional)

Displays the virtual terminal configuration.

Step 6

(Optional) copy running-config startup-config

Example:

switch(config)# copy running-config startup-config
 (Optional)

Copies the running configuration to the startup configuration.

Configuring the Session Limit

You can limit the number of virtual terminal sessions on your Cisco NX-OS device.

SUMMARY STEPS

  1. configure terminal
  2. line vty
  3. session-limit sessions
  4. exit
  5. (Optional) show running-config all | being vty
  6. (Optional) copy running-config startup-config

DETAILED STEPS

  Command or Action Purpose
Step 1

configure terminal

Example:

switch# configure terminal
switch(config)#

Enters global configuration mode.
Step 2

line vty

Example:

switch# line vty
switch(config-line)#

Enters line configuration mode.
Step 3

session-limit sessions

Example:

switch(config-line)# session-limit 10

Configures the maximum number of virtual sessions for the Cisco NX-OS device. The range is from 1 to 60. The default is 32.

Step 4

exit

Example:

switch(config-line)# exit
switch(config)#

Exits line configuration mode.
Step 5

(Optional) show running-config all | being vty

Example:

switch(config)# show running-config all | begin vty
 (Optional)

Displays the virtual terminal configuration.
Step 6

(Optional) copy running-config startup-config

Example:

switch(config)# copy running-config startup-config
 (Optional)

Copies the running configuration to the startup configuration.

Configuring Modem Connections

You can connect a modem to either the COM1 port or the console port.

We recommend that you use the COM1 port to connect the modem.

Enabling a Modem Connection

You must enable the modem connection on the port before you can use the modem.

Before you begin

Log in to the console port.

SUMMARY STEPS

  1. configure terminal
  2. Enter one of the following commands:
  3. modem in
  4. exit
  5. (Optional) show line
  6. (Optional) copy running-config startup-config

DETAILED STEPS

  Command or Action Purpose
Step 1

configure terminal

Example:

switch# configure terminal
switch(config)#

Enters global configuration mode.
Step 2

Enter one of the following commands:

Command Purpose
line com1 Enters COM1 configuration mode.
line console Enters console configuration mode.

Example:

switch# line com1
switch(config-com1)#

Enters COM1 configuration mode or console configuration mode.
Step 3

modem in

Example:

switch(config-com1)# modem in

Enables modem input on the COM1 or console port.
Step 4

exit

Example:

switch(config-com1)# exit
switch(config)#

Exits COM1 or console configuration mode.
Step 5

(Optional) show line

Example:

switch(config)# show line
 (Optional)

Displays the console and COM1 settings.
Step 6

(Optional) copy running-config startup-config

Example:

switch(config)# copy running-config startup-config
 (Optional)

Copies the running configuration to the startup configuration.

Downloading the Default Initialization String

The Cisco NX-OS software provides a default initialization string that you can download for connecting with the modem. The default initialization string is ATE0Q1&D2&C1S0=1\015.

Before you begin

Log in to the console port.

SUMMARY STEPS

  1. configure terminal
  2. Enter one of the following commands:
  3. modem init-string default
  4. exit
  5. (Optional) show line
  6. (Optional) copy running-config startup-config

DETAILED STEPS

  Command or Action Purpose
Step 1

configure terminal

Example:

switch# configure terminal
switch(config)#

Enters global configuration mode.
Step 2

Enter one of the following commands:

Option Description
line com1 Enters COM1 configuration mode.
line console Enters console configuration mode.

Example:

switch# line com1
switch(config-com1)#
Step 3

modem init-string default

Example:

switch(config-com1)# modem init-string default

Writes the default initialization string to the modem.
Step 4

exit

Example:

switch(config-com1)# exit
switch(config)#

Exits COM1 or console configuration mode.
Step 5

(Optional) show line

Example:

switch(config)# show line
 (Optional)

Displays the COM1 and console settings.
Step 6

(Optional) copy running-config startup-config

Example:

switch(config)# copy running-config startup-config
 (Optional)

Copies the running configuration to the startup configuration.

Configuring and Downloading a User-Specified Initialization String

You can configure and download your own initialization when the default initialization string is not compatible with your modem.

Before you begin

Log in to the console port.

SUMMARY STEPS

  1. configure terminal
  2. Enter one of the following commands:
  3. modem set-string user-input string
  4. modem init-string user-input
  5. exit
  6. (Optional) show line
  7. (Optional) copy running-config startup-config

DETAILED STEPS

  Command or Action Purpose
Step 1

configure terminal

Example:

switch# configure terminal
switch(config)#

Enters global configuration mode.
Step 2

Enter one of the following commands:

Option Description
line com1 Enters COM1 configuration mode.
line console Enters console configuration mode.

Example:

switch# line com1
switch(config-com1)#
Step 3

modem set-string user-input string

Example:

switch(config-com1)# modem set-string 
user-input ATE0Q1&D2&C1S0=3\015

Sets the user-specified initialization string for the COM1 or console port. The initialization string is alphanumeric and case sensitive, can contain special characters, and has a maximum of 100 characters.

Note 

You must first set the user-input string before initializing the string.
Step 4

modem init-string user-input

Example:

switch(config-com1)# modem init-string 
user-input

Writes the user-specified initialization string to the modem connected to the COM1 or console port.

Step 5

exit

Example:

switch(config-com1)# exit
switch(config)#

Exits COM1 or console configuration mode.
Step 6

(Optional) show line

Example:

switch(config)# show line
 (Optional)

Displays the COM1 and console settings.
Step 7

(Optional) copy running-config startup-config

Example:

switch(config)# copy running-config 
startup-config
 (Optional)

Copies the running configuration to the startup configuration.

Initializing a Modem for a Powered-Up Cisco NX-OS Device

If you connect a modem to a powered-up physical device, you must initialize the modem before you can use it.

Before you begin

After waiting until the Cisco NX-OS device has completed the boot sequence and the system image is running, connect the modem to either the COM1 port or the console port on the device.

Enable the modem connection on the port.

SUMMARY STEPS

  1. modem connect line {com1 | console }

DETAILED STEPS

Command or Action Purpose

modem connect line {com1 | console }

Example:

switch# modem connect line com1

Initializes the modem connected to the device.

Clearing Terminal Sessions

You can clear terminal sessions on the Cisco NX-OS device.

SUMMARY STEPS

  1. (Optional) show users
  2. clear line name

DETAILED STEPS

  Command or Action Purpose
Step 1

(Optional) show users

Example:

switch# show users
 (Optional)

Displays the user sessions on the device.
Step 2

clear line name

Example:

switch# clear line pts/0

Clears a terminal session on a specific line. The line name is case sensitive.

Displaying Terminal and Session Information

To display terminal and session information, perform one of the following tasks:

Command

Purpose

show terminal

Displays terminal settings.

show line

Displays the COM1 and console ports settings.

show users

Displays virtual terminal sessions.

show running-config [all ]

Displays the user account configuration in the running configuration. The all keyword displays the default values for the user accounts.

For detailed information about the fields in the output from these commands, see the Cisco Nexus command reference guide for your device.

Default Settings for Terminal Display and Session Parameters

This table lists the default settings for terminal displays and session parameters.

Table 1. Default Terminal Display and Session Parameter Settings

Parameters

Default

Terminal type

ansi

Terminal length

0 lines for console sessions

31 lines for virtual terminal sessions

Terminal width

80 columns

Terminal inactive session timeout

Disabled (0 minutes)

Console session data bits

8

Console inactive session timeout

Disabled (0 minutes)

Console session parity

none

Console session speed

11520 bps

Console session stop bits

1

COM1 session data bits

8

COM1 hardware flow control

Enabled

COM1 session parity

none

COM1 session speed

9600 bps

COM1 session stop bits

1

Virtual terminal inactive session timeout

Disabled (0 minutes)

Virtual terminal sessions limit

32

Modem default initialization string

ATE0Q1&D2&C1S0=1\015