Administrator Guide

Troubleshoot an Over-Temperature Condition..................................................................................................... 339
Troubleshooting Packet Loss........................................................................................................................................ 341
Displaying Drop Counters........................................................................................................................................ 341
Displaying Dataplane Statistics...............................................................................................................................342
Displaying Line-Card Counters...............................................................................................................................344
Accessing Application Core Dumps.............................................................................................................................344
Mini Core Dumps........................................................................................................................................................... 345
Full Kernel Core Dumps.................................................................................................................................................346
Enabling TCP Dumps.....................................................................................................................................................346
Accessing Port Extender Core and Mini Core Dumps...............................................................................................347
13 Dynamic Host Conguration Protocol (DHCP).........................................................................................348
DHCP Packet Format and Options............................................................................................................................. 348
Assign an IP Address using DHCP...............................................................................................................................350
Implementation Information.......................................................................................................................................... 351
Congure the System to be a DHCP Server.............................................................................................................. 351
Conguring the Server for Automatic Address Allocation..................................................................................352
Specifying a Default Gateway................................................................................................................................ 353
Congure a Method of Hostname Resolution..................................................................................................... 354
Using DNS for Address Resolution........................................................................................................................354
Using NetBIOS WINS for Address Resolution..................................................................................................... 354
Creating Manual Binding Entries............................................................................................................................354
Debugging the DHCP Server.................................................................................................................................355
Using DHCP Clear Commands.............................................................................................................................. 355
Congure the System to be a Relay Agent................................................................................................................ 355
Congure the System to be a DHCP Client............................................................................................................... 357
DHCP Client on a Management Interface............................................................................................................ 357
DHCP Client Operation with Other Features....................................................................................................... 357
DHCP Relay When DHCP Server and Client are in Dierent VRFs........................................................................358
Conguring Route Leaking between VRFs on DHCP Relay Agent................................................................... 359
Non-default VRF conguration for DHCPv6 helper address...................................................................................360
Conguring DHCP relay source interface...................................................................................................................360
Global DHCP relay source IPv4 or IPv6 conguration .......................................................................................360
Interface level DHCP relay source IPv4 or IPv6 conguration .......................................................................... 361
Congure Secure DHCP...............................................................................................................................................362
Option 82..................................................................................................................................................................362
DHCPv6 relay agent options..................................................................................................................................363
DHCP Snooping.......................................................................................................................................................363
Drop DHCP Packets on Snooped VLANs Only....................................................................................................365
Dynamic ARP Inspection........................................................................................................................................ 366
Conguring Dynamic ARP Inspection....................................................................................................................367
Source Address Validation............................................................................................................................................ 368
Enabling IP Source Address Validation..................................................................................................................368
DHCP MAC Source Address Validation................................................................................................................ 369
Enabling IP+MAC Source Address Validation.......................................................................................................369
Viewing the Number of SAV Dropped Packets....................................................................................................370
Contents
11