Administrator Guide

Protocol Overview......................................................................................................................................................... 784
Conguring Rapid Spanning Tree.................................................................................................................................784
Related Conguration Tasks................................................................................................................................... 784
Important Points to Remember....................................................................................................................................784
RSTP and VLT..........................................................................................................................................................785
Conguring Interfaces for Layer 2 Mode....................................................................................................................785
Enabling Rapid Spanning Tree Protocol Globally........................................................................................................786
Adding and Removing Interfaces................................................................................................................................. 788
Modifying Global Parameters....................................................................................................................................... 788
Enabling SNMP Traps for Root Elections and Topology Changes.....................................................................790
Modifying Interface Parameters.................................................................................................................................. 790
Enabling SNMP Traps for Root Elections and Topology Changes...........................................................................790
Inuencing RSTP Root Selection.................................................................................................................................790
Conguring an EdgePort............................................................................................................................................... 791
Conguring Fast Hellos for Link State Detection.......................................................................................................792
47 Software-Dened Networking (SDN)...................................................................................................... 793
48 Security................................................................................................................................................... 794
AAA Accounting.............................................................................................................................................................794
Conguration Task List for AAA Accounting........................................................................................................ 794
AAA Authentication....................................................................................................................................................... 796
Conguration Task List for AAA Authentication...................................................................................................797
Obscuring Passwords and Keys...................................................................................................................................800
AAA Authorization.........................................................................................................................................................800
Privilege Levels Overview.......................................................................................................................................800
Conguration Task List for Privilege Levels...........................................................................................................801
RADIUS...........................................................................................................................................................................805
RADIUS Authentication.......................................................................................................................................... 805
Conguration Task List for RADIUS...................................................................................................................... 806
TACACS+........................................................................................................................................................................ 810
Conguration Task List for TACACS+....................................................................................................................810
TACACS+ Remote Authentication.......................................................................................................................... 811
Command Authorization..........................................................................................................................................813
Protection from TCP Tiny and Overlapping Fragment Attacks................................................................................813
Enabling SCP and SSH.................................................................................................................................................. 813
Using SCP with SSH to Copy a Software Image................................................................................................. 814
Removing the RSA Host Keys and Zeroizing Storage ........................................................................................ 815
Conguring When to Re-generate an SSH Key .................................................................................................. 815
Conguring the SSH Server Key Exchange Algorithm........................................................................................816
Conguring the HMAC Algorithm for the SSH Server........................................................................................816
Conguring the HMAC Algorithm for the SSH Client..........................................................................................817
Conguring the SSH Server Cipher List................................................................................................................817
Conguring the SSH Client Cipher List................................................................................................................. 818
Secure Shell Authentication....................................................................................................................................818
Troubleshooting SSH................................................................................................................................................821
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