Dell PowerSwitch S4820T Configuration Guide for the S4820T System 9.100.0 - Page 751

If the IP address in the RSA key does not match the IP address from which you attempt to log in, the following message appears. In this case, verify that the name and IP address of the client is contained in the file /etc/hosts: RSA Authentication Error. Telnet To use Telnet with SSH, first enable SSH, as previously described. By default, the Telnet daemon is enabled. If you want to disable the Telnet daemon, use the following command, or disable Telnet in the startup config. To enable or disable the Telnet daemon, use the [no] ip telnet server enable command. 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 vrfinstance-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 Dell(conf)#ip telnet server enable Dell(conf)#no ip telnet server enable VTY Line and Access-Class Configuration Various methods are available to restrict VTY access in Dell Networking OS. These depend on which authentication scheme you use - line, local, or remote. Table 79. VTY Access Authentication Method Line Local TACACS+ RADIUS VTY access-class support? YES NO YES YES Username access-class support? NO YES NO NO Dell Networking OS provides several ways to configure access classes for VTY lines, including: • VTY Line Local Authentication and Authorization • VTY Line Remote Authentication and Authorization Remote authorization support? NO NO YES (with Dell Networking OS version 5.2.1.0 and later) YES (with Dell Networking OS version 6.1.1.0 and later) VTY Line Local Authentication and Authorization Dell Networking OS 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. Dell Networking OS can assign different access classes to different users by username. Until users attempt to log in, Dell Networking OS 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 Security 751