Administrator Guide

The Telnet server or client is VRF-aware. You can enable a Telnet server or client to listen to a specific VRF by using the vrf
vrf-instance-name parameter in the telnet command. This capability enables a Telent server or client to look up the
correct routing table and establish a connection.
Example of Using Telnet for Remote Login
DellEMC(conf)#ip telnet server enable
DellEMC(conf)#no ip telnet server enable
VTY Line and Access-Class Configuration
Various methods are available to restrict VTY access in . These depend on which authentication scheme you use — line, local, or
remote.
Table 101. VTY Access
Authentication Method VTY access-class support? Username access-class
support?
Remote authorization
support?
Line YES NO NO
Local NO YES NO
TACACS+ YES NO YES (with version 5.2.1.0 and
later)
RADIUS YES NO YES (with version 6.1.1.0 and
later)
provides several ways to configure access classes for VTY lines, including:
● VTY Line Local Authentication and Authorization
● VTY Line Remote Authentication and Authorization
VTY Line Local Authentication and Authorization
retrieves the access class from the local database.
To use this feature:
1. Create a username.
2. Enter a password.
3. Assign an access class.
4. Enter a privilege level.
You can assign line authentication on a per-VTY basis; it is a simple password authentication, using an access-class as
authorization.
Configure local authentication globally and configure access classes on a per-user basis.
can assign different access classes to different users by username. Until users attempt to log in, does not know if they will be
assigned a VTY line. This means that incoming users always see a login prompt even if you have excluded them from the VTY
line with a deny-all access class. After users identify themselves, retrieves the access class from the local database and applies
it. ( then can close the connection if a user is denied access.)
NOTE:
If a VTY user logs in with RADIUS authentication, the privilege level is applied from the RADIUS server only if you
configure RADIUS authentication.
The following example shows how to allow or deny a Telnet connection to a user. Users see a login prompt even if they cannot
log in. No access class is configured for the VTY line. It defaults from the local database.
Example of Configuring VTY Authorization Based on Access Class Retrieved from a Local Database (Per User)
DellEMC(conf)#user gooduser password abc privilege 10 access-class permitall
DellEMC(conf)#user baduser password abc privilege 10 access-class denyall
DellEMC(conf)#
DellEMC(conf)#aaa authentication login localmethod local
DellEMC(conf)#
Security
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