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Table Of Contents
Chapter 45: Security................................................................................................................. 739
AAA Accounting...............................................................................................................................................................739
Configuration Task List for AAA Accounting......................................................................................................739
RADIUS Accounting...................................................................................................................................................741
AAA Authentication........................................................................................................................................................ 746
Configuration Task List for AAA Authentication................................................................................................746
Obscuring Passwords and Keys...................................................................................................................................749
AAA Authorization...........................................................................................................................................................749
Privilege Levels Overview....................................................................................................................................... 750
Configuration Task List for Privilege Levels.......................................................................................................750
RADIUS..............................................................................................................................................................................753
RADIUS Authentication............................................................................................................................................754
Configuration Task List for RADIUS..................................................................................................................... 755
Support for Change of Authorization and Disconnect Messages packets................................................. 758
TACACS+..........................................................................................................................................................................768
Configuration Task List for TACACS+................................................................................................................. 768
TACACS+ Remote Authentication........................................................................................................................769
Command Authorization.......................................................................................................................................... 770
Protection from TCP Tiny and Overlapping Fragment Attacks............................................................................771
Enabling SCP and SSH................................................................................................................................................... 771
Using SCP with SSH to Copy a Software Image...............................................................................................772
Removing the RSA Host Keys and Zeroizing Storage .....................................................................................772
Configuring When to Re-generate an SSH Key ................................................................................................773
Configuring the SSH Server Key Exchange Algorithm.....................................................................................773
Configuring the HMAC Algorithm for the SSH Server.....................................................................................774
Configuring the HMAC Algorithm for the SSH Client...................................................................................... 774
Configuring the SSH Server Cipher List..............................................................................................................775
Configuring the SSH Client Cipher List............................................................................................................... 775
Configuring DNS in the SSH Server..................................................................................................................... 776
Secure Shell Authentication....................................................................................................................................776
Troubleshooting SSH................................................................................................................................................778
Telnet................................................................................................................................................................................. 778
VTY Line and Access-Class Configuration................................................................................................................779
VTY Line Local Authentication and Authorization.............................................................................................779
VTY Line Remote Authentication and Authorization........................................................................................780
VTY MAC-SA Filter Support...................................................................................................................................780
Role-Based Access Control.......................................................................................................................................... 780
Overview of RBAC.....................................................................................................................................................781
User Roles................................................................................................................................................................... 783
AAA Authentication and Authorization for Roles.............................................................................................. 786
Role Accounting.........................................................................................................................................................788
Display Information About User Roles..................................................................................................................789
Two Factor Authentication (2FA)...............................................................................................................................790
Handling Access-Challenge Message....................................................................................................................791
Configuring Challenge Response Authentication for SSHv2.......................................................................... 791
SMS-OTP Mechanism.............................................................................................................................................. 791
Configuring the System to Drop Certain ICMP Reply Messages........................................................................792
SSH Lockout Settings....................................................................................................................................................793
Dell EMC Networking OS Security Hardening......................................................................................................... 793
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