Administrator Guide

44 Rapid Spanning Tree Protocol (RSTP).....................................................................................................696
Protocol Overview.........................................................................................................................................................696
Conguring Rapid Spanning Tree................................................................................................................................ 696
Related Conguration Tasks...................................................................................................................................696
Important Points to Remember................................................................................................................................... 696
RSTP and VLT.......................................................................................................................................................... 697
Conguring Interfaces for Layer 2 Mode....................................................................................................................697
Enabling Rapid Spanning Tree Protocol Globally........................................................................................................698
Adding and Removing Interfaces.................................................................................................................................700
Modifying Global Parameters....................................................................................................................................... 700
Enabling SNMP Traps for Root Elections and Topology Changes.....................................................................702
Modifying Interface Parameters...................................................................................................................................702
Enabling SNMP Traps for Root Elections and Topology Changes...........................................................................702
Inuencing RSTP Root Selection.................................................................................................................................702
Conguring an EdgePort.............................................................................................................................................. 703
Conguring Fast Hellos for Link State Detection.......................................................................................................704
45 Software-Dened Networking (SDN)...................................................................................................... 705
46 Security................................................................................................................................................... 706
AAA Accounting.............................................................................................................................................................706
Conguration Task List for AAA Accounting........................................................................................................ 706
AAA Authentication.......................................................................................................................................................708
Conguration Task List for AAA Authentication.................................................................................................. 709
Obscuring Passwords and Keys....................................................................................................................................712
AAA Authorization..........................................................................................................................................................712
Privilege Levels Overview........................................................................................................................................712
Conguration Task List for Privilege Levels...........................................................................................................713
RADIUS............................................................................................................................................................................ 717
RADIUS Authentication............................................................................................................................................717
Conguration Task List for RADIUS....................................................................................................................... 718
TACACS+........................................................................................................................................................................722
Conguration Task List for TACACS+................................................................................................................... 722
TACACS+ Remote Authentication.........................................................................................................................723
Command Authorization......................................................................................................................................... 725
Protection from TCP Tiny and Overlapping Fragment Attacks............................................................................... 725
Enabling SCP and SSH..................................................................................................................................................725
Using SCP with SSH to Copy a Software Image.................................................................................................726
Removing the RSA Host Keys and Zeroizing Storage ........................................................................................727
Conguring When to Re-generate an SSH Key .................................................................................................. 727
Conguring the SSH Server Key Exchange Algorithm....................................................................................... 728
Conguring the HMAC Algorithm for the SSH Server....................................................................................... 728
Conguring the SSH Server Cipher List............................................................................................................... 729
Secure Shell Authentication................................................................................................................................... 729
Troubleshooting SSH............................................................................................................................................... 732
Contents
23