The following examples show how to cause the network access server to request authorization information from a TACACS+ security server before allowing a user to establish a reverse Telnet session:
aaa new-model
aaa authentication login default group tacacs+
aaa authorization reverse-access default group tacacs+
!
tacacs-server host 172.31.255.0
tacacs-server timeout 90
tacacs-server key goaway
The lines in this sample TACACS+ reverse Telnet authorization configuration are defined as follows:
The aaa new-model command enables AAA.
The aaa authentication login default group tacacs+ command specifies TACACS+ as the default method for user authentication during login.
The aaa authorization reverse-access default group tacacs+ command specifies TACACS+ as the method for user authorization when trying to establish a reverse Telnet session.
The tacacs-server host command identifies the TACACS+ server.
The tacacs-server timeoutcommand sets the interval of time that the network access server waits for the TACACS+ server to reply.
The tacacs-server key command defines the encryption key used for all TACACS+ communications between the network access server and the TACACS+ daemon.
The following example shows how to configure a generic TACACS+ server to grant a user, pat, reverse Telnet access to port tty2 on the network access server named “maple” and to port tty5 on the network access server named “oak”:
user = pat
login = cleartext lab
service = raccess {
port#1 = maple/tty2
port#2 = oak/tty5
 Note |
In this example, “maple” and “oak” are the configured host names of network access servers, not DNS names or alias.
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The following example shows how to configure the TACACS+ server (CiscoSecure) to grant a user named pat reverse Telnet access:
user = pat
profile_id = 90
profile_cycle = 1
member = Tacacs_Users
service=shell {
default cmd=permit
}
service=raccess {
allow “c2511e0” “tty1” “.*”
refuse “.*” “.*” “.*”
password = clear “goaway”
 Note |
CiscoSecure only supports reverse Telnet using the command line interface in versions 2.1(x) through version 2.2(1).
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An empty “service=raccess {}” clause permits a user to have unconditional access to network access server ports for reverse Telnet. If no “service=raccess” clause exists, the user is denied access to any port for reverse Telnet.
The following example shows how to cause the network access server to request authorization from a RADIUS security server before allowing a user to establish a reverse Telnet session:
aaa new-model
aaa authentication login default group radius
aaa authorization reverse-access default group radius
!
radius-server host 172.31.255.0
radius-server key go away
auth-port 1645 acct-port 1646
The lines in this sample RADIUS reverse Telnet authorization configuration are defined as follows:
The aaa new-model command enables AAA.
The aaa authentication login default group radius command specifies RADIUS as the default method for user authentication during login.
The aaa authorization reverse-access default group radius command specifies RADIUS as the method for user authorization when trying to establish a reverse Telnet session.
The radius-server host command identifies the RADIUS server.
The radius-server key command defines the encryption key used for all RADIUS communications between the network access server and the RADIUS daemon.
The following example shows how to send a request to the RADIUS server to grant a user named “pat” reverse Telnet access at port tty2 on the network access server named “maple”:
Username = “pat”
Password = “goaway”
User-Service-Type = Shell-User
cisco-avpair = “raccess:port#1=maple/tty2”
The syntax "raccess:port=any/any" permits a user to have unconditional access to network access server ports for reverse Telnet. If no "raccess:port={nasname
}/{tty number
}" clause exists in the user profile, the user is denied access to reverse Telnet on all ports.