Administrator Guide

Protocol Overview......................................................................................................................................................... 734
Conguring Rapid Spanning Tree.................................................................................................................................734
Related Conguration Tasks................................................................................................................................... 734
Important Points to Remember....................................................................................................................................734
RSTP and VLT..........................................................................................................................................................735
Conguring Interfaces for Layer 2 Mode....................................................................................................................735
Enabling Rapid Spanning Tree Protocol Globally........................................................................................................736
Adding and Removing Interfaces................................................................................................................................. 738
Modifying Global Parameters....................................................................................................................................... 738
Enabling SNMP Traps for Root Elections and Topology Changes.....................................................................740
Modifying Interface Parameters...................................................................................................................................740
Enabling SNMP Traps for Root Elections and Topology Changes...........................................................................740
Inuencing RSTP Root Selection.................................................................................................................................740
Conguring an EdgePort............................................................................................................................................... 741
Conguring Fast Hellos for Link State Detection.......................................................................................................742
43 Software-Dened Networking (SDN)...................................................................................................... 743
44 Security................................................................................................................................................... 744
AAA Accounting............................................................................................................................................................. 744
Conguration Task List for AAA Accounting........................................................................................................ 744
AAA Authentication....................................................................................................................................................... 746
Conguration Task List for AAA Authentication...................................................................................................747
Obscuring Passwords and Keys...................................................................................................................................750
AAA Authorization......................................................................................................................................................... 750
Privilege Levels Overview.......................................................................................................................................750
Conguration Task List for Privilege Levels...........................................................................................................751
RADIUS........................................................................................................................................................................... 755
RADIUS Authentication...........................................................................................................................................755
Conguration Task List for RADIUS...................................................................................................................... 756
TACACS+........................................................................................................................................................................760
Conguration Task List for TACACS+................................................................................................................... 760
TACACS+ Remote Authentication..........................................................................................................................761
Command Authorization......................................................................................................................................... 763
Protection from TCP Tiny and Overlapping Fragment Attacks............................................................................... 763
Enabling SCP and SSH..................................................................................................................................................763
Using SCP with SSH to Copy a Software Image.................................................................................................764
Removing the RSA Host Keys and Zeroizing Storage ........................................................................................765
Conguring When to Re-generate an SSH Key ..................................................................................................765
Conguring the SSH Server Key Exchange Algorithm....................................................................................... 766
Conguring the HMAC Algorithm for the SSH Server....................................................................................... 766
Conguring the HMAC Algorithm for the SSH Client.........................................................................................767
Conguring the SSH Server Cipher List............................................................................................................... 767
Conguring the SSH Client Cipher List.................................................................................................................768
Secure Shell Authentication................................................................................................................................... 768
Troubleshooting SSH................................................................................................................................................771
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