Owners Manual

ip ssh challenge-response-authentication enable
2. View the configuration.
EXEC mode
show ip ssh
Dell# show ip ssh
SSH server : enabled.
SSH server version : v1 and v2.
SSH server vrf : default.
SSH server ciphers : aes256-ctr,aes256-cbc,aes192-ctr,aes192-cbc,aes128-
ctr,aes128-cbc,3des-cbc.
SSH server macs : hmac-sha2-256,hmac-sha1,hmac-sha1-96,hmac-md5,hmac-md5-96.
SSH server kex algorithms : diffie-hellman-group-exchange-sha1,diffie-hellman-group1-
sha1,diffie-hellman-group14-sha1.
Password Authentication : enabled.
Hostbased Authentication : disabled.
RSA Authentication : disabled.
Challenge Response Auth : enabled.
Vty Encryption HMAC Remote IP
2 aes128-cbc hmac-md5 10.16.127.141
4 aes128-cbc hmac-md5 10.16.127.141
* 5 aes128-cbc hmac-md5 10.16.127.141
Dell#
SMS-OTP Mechanism
A short message service one time password (SMS-OTP) is a free RADIUS module to implement two factor authentication.
There are multiple 2FA mechanisms that can be deployed with the RADIUS. Mechanisms such as the Google authenticator do
not rely on the Access-Challenge message and the SMS-OTP module rely on the Access-challenge message. The main objective
of this feature is to handle the Access-Challenge messages and sends the Access-Request message with user’s response.
This module requires NAS for handling the access challenge from the RADIUS server. NAS sends the input OTP in an
Access-Request to the RADIUS server, and the user authentication succeeds or fails depending upon the Access-Accept or
Access-Reject response received at NAS from the RADIUS server.
Configuring the System to Drop Certain ICMP Reply
Messages
You can configure the Dell Networking OS to drop ICMP reply messages. When you configure the drop icmp command, the
system drops the ICMP reply messages from the front end and management interfaces. By default, the Dell Networking OS
responds to all the ICMP messages.
● Drop the ICMP or ICMPv6 message type.
drop {icmp | icmp6}
CONFIGURATION mode.
You can configure the Dell Networking OS to suppress the following ICMPv4 and ICMP6 message types:
Table 104. Suppressed ICMP message types
ICMPv4 message types
Echo reply (0)
All sub types of destination unreachable (3)
Source quench (4)
Redirect (5)
Security 875