Users Guide

Conguring Rapid Spanning Tree.................................................................................................................................798
Related Conguration Tasks................................................................................................................................... 798
Important Points to Remember....................................................................................................................................798
RSTP and VLT..........................................................................................................................................................799
Conguring Interfaces for Layer 2 Mode....................................................................................................................799
Enabling Rapid Spanning Tree Protocol Globally....................................................................................................... 800
Adding and Removing Interfaces.................................................................................................................................802
Modifying Global Parameters....................................................................................................................................... 802
Enabling SNMP Traps for Root Elections and Topology Changes.....................................................................804
Modifying Interface Parameters.................................................................................................................................. 804
Enabling SNMP Traps for Root Elections and Topology Changes...........................................................................804
Inuencing RSTP Root Selection................................................................................................................................ 805
Conguring an EdgePort.............................................................................................................................................. 805
Conguring Fast Hellos for Link State Detection...................................................................................................... 806
46 Software-Dened Networking (SDN)...................................................................................................... 807
47 Security................................................................................................................................................... 808
AAA Accounting.............................................................................................................................................................808
Conguration Task List for AAA Accounting........................................................................................................808
AAA Authentication........................................................................................................................................................810
Conguration Task List for AAA Authentication....................................................................................................811
Obscuring Passwords and Keys....................................................................................................................................814
AAA Authorization..........................................................................................................................................................814
Privilege Levels Overview........................................................................................................................................814
Conguration Task List for Privilege Levels...........................................................................................................815
RADIUS............................................................................................................................................................................819
RADIUS Authentication........................................................................................................................................... 819
Conguration Task List for RADIUS...................................................................................................................... 820
Support for Change of Authorization and Disconnect Messages packets...................................................... 823
TACACS+........................................................................................................................................................................833
Conguration Task List for TACACS+................................................................................................................... 833
TACACS+ Remote Authentication.........................................................................................................................834
Command Authorization.........................................................................................................................................835
Protection from TCP Tiny and Overlapping Fragment Attacks............................................................................... 836
Enabling SCP and SSH................................................................................................................................................. 836
Using SCP with SSH to Copy a Software Image.................................................................................................837
Removing the RSA Host Keys and Zeroizing Storage ....................................................................................... 838
Conguring When to Re-generate an SSH Key ..................................................................................................838
Conguring the SSH Server Key Exchange Algorithm....................................................................................... 838
Conguring the HMAC Algorithm for the SSH Server.......................................................................................839
Conguring the SSH Server Cipher List...............................................................................................................839
Conguring DNS in the SSH Server..................................................................................................................... 840
Secure Shell Authentication................................................................................................................................... 840
Troubleshooting SSH...............................................................................................................................................843
Telnet...............................................................................................................................................................................843
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