Concept Guide

If any user is already in CONFIGURATION mode when while a lock is in place, the following appears on their terminal (message 2): %

Error: Can't lock configuration mode exclusively since the following users are currently

configuring the system: User "admin" on line vty1 ( 10.1.1.1 ).

NOTE: The CONFIGURATION mode lock corresponds to a VTY session, not a user. Therefore, if you congure a lock and then

exit CONFIGURATION mode, and another user enters CONFIGURATION mode, when you attempt to re-enter CONFIGURATION

mode, you are denied access even though you are the one that congured the lock.

NOTE: If your session times out and you return to EXEC mode, the CONFIGURATION mode lock is uncongured.

Limit Concurrent Login Sessions

Dell Networking OS enables you to limit the number of concurrent login sessions of users on VTY, Aux, and console lines. You can also clear

any of your existing sessions when you reach the maximum permitted number of concurrent sessions.

By default, you can use all 10 VTY lines, one console line, and one Aux line. You can limit the number of available sessions using the login

concurrent-session limit command and so restrict users to that specic number of sessions. You can optionally congure the

system to provide an option to the users to clear any of their existing sessions.

Restrictions for Limiting the Number of Concurrent Sessions

These restrictions apply for limiting the number of concurrent sessions:

• Only the system and security administrators can limit the number of concurrent sessions and enable the clear-line option.

• Users can clear their existing sessions only if the system is congured with the login concurrent-session clear-line

enable command.

Conguring Concurrent Session Limit

To congure concurrent session limit, follow this procedure:

• Limit the number of concurrent sessions for all users.

CONFIGURATION mode

Example of Conguring Concurrent Session Limit

The following example limits the permitted number of concurrent login sessions to 4.

Dell(config)#login concurrent-session limit 4

Enabling the System to Clear Existing Sessions

To enable the system to clear existing login sessions, follow this procedure:

• Use the following command.

CONFIGURATION mode

Management