Concept Guide

Table Of Contents
RADIUS Accounting..................................................................................................................................................684
AAA Authentication........................................................................................................................................................ 689
Configuration Task List for AAA Authentication............................................................................................... 689
Obscuring Passwords and Keys.................................................................................................................................. 692
AAA Authorization.......................................................................................................................................................... 692
Privilege Levels Overview....................................................................................................................................... 692
Configuration Task List for Privilege Levels.......................................................................................................693
RADIUS..............................................................................................................................................................................696
RADIUS Authentication............................................................................................................................................697
Configuration Task List for RADIUS.....................................................................................................................698
RADIUS-assigned dynamic access control lists.................................................................................................700
Support for Change of Authorization and Disconnect Messages packets................................................. 705
TACACS+...........................................................................................................................................................................715
Configuration Task List for TACACS+..................................................................................................................715
TACACS+ Remote Authentication.........................................................................................................................717
Command Authorization...........................................................................................................................................718
Protection from TCP Tiny and Overlapping Fragment Attacks........................................................................... 718
Enabling SCP and SSH................................................................................................................................................... 718
Using SCP with SSH to Copy a Software Image............................................................................................... 719
Removing the RSA Host Keys and Zeroizing Storage .................................................................................... 720
Configuring When to Re-generate an SSH Key ............................................................................................... 720
Configuring the SSH Server Key Exchange Algorithm.................................................................................... 720
Configuring the HMAC Algorithm for the SSH Server..................................................................................... 721
Configuring the HMAC Algorithm for the SSH Client.......................................................................................721
Configuring the SSH Server Cipher List..............................................................................................................722
Configuring the SSH Client Cipher List............................................................................................................... 722
Configuring DNS in the SSH Server..................................................................................................................... 723
Secure Shell Authentication....................................................................................................................................723
Troubleshooting SSH................................................................................................................................................725
Telnet................................................................................................................................................................................. 726
VTY Line and Access-Class Configuration................................................................................................................726
VTY Line Local Authentication and Authorization.............................................................................................726
VTY Line Remote Authentication and Authorization........................................................................................ 727
VTY MAC-SA Filter Support................................................................................................................................... 727
Role-Based Access Control.......................................................................................................................................... 727
Overview of RBAC.................................................................................................................................................... 728
User Roles...................................................................................................................................................................730
AAA Authentication and Authorization for Roles...............................................................................................733
Role Accounting.........................................................................................................................................................735
Display Information About User Roles..................................................................................................................736
Two Factor Authentication (2FA)...............................................................................................................................737
Handling Access-Challenge Message...................................................................................................................738
Configuring Challenge Response Authentication for SSHv2..........................................................................738
SMS-OTP Mechanism..............................................................................................................................................738
Configuring the System to Drop Certain ICMP Reply Messages........................................................................739
Dell EMC Networking OS Security Hardening......................................................................................................... 740
Dell EMC Networking OS Image Verification..................................................................................................... 740
Startup Configuration Verification.........................................................................................................................741
Configuring the root User Password....................................................................................................................742
Locking Access to GRUB Interface...................................................................................................................... 743
Contents
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