Concept Guide

Clearing Interface Counters................................................................................................................................... 458
Discard Counters........................................................................................................................................................... 459
Display discard counters......................................................................................................................................... 459
22 Internet Protocol Security (IPSec)........................................................................................................... 461
Conguring IPSec ..........................................................................................................................................................461
23 IPv4 Routing............................................................................................................................................463
IP Addresses...................................................................................................................................................................464
Implementation Information....................................................................................................................................464
Conguration Tasks for IP Addresses..........................................................................................................................464
Assigning IP Addresses to an Interface.......................................................................................................................464
Conguring Static Routes............................................................................................................................................ 465
Adding description for IPv4 and IPv6 static routes.............................................................................................466
Congure Static Routes for the Management Interface.......................................................................................... 467
IPv4 Path MTU Discovery Overview...........................................................................................................................467
Packet handling during MTU mismatch................................................................................................................468
Using the Congured Source IP Address in ICMP Messages..................................................................................468
Conguring the ICMP Source Interface............................................................................................................... 468
Conguring the Duration to Establish a TCP Connection........................................................................................ 469
Enabling Directed Broadcast........................................................................................................................................ 469
Resolution of Host Names............................................................................................................................................469
Enabling Dynamic Resolution of Host Names............................................................................................................470
Specifying the Local System Domain and a List of Domains....................................................................................470
Conguring DNS with Traceroute................................................................................................................................ 471
ARP.................................................................................................................................................................................. 471
Conguration Tasks for ARP........................................................................................................................................ 472
Conguring Static ARP Entries....................................................................................................................................472
Enabling Proxy ARP.......................................................................................................................................................472
Clearing ARP Cache...................................................................................................................................................... 473
ARP Learning via Gratuitous ARP................................................................................................................................473
Enabling ARP Learning via Gratuitous ARP................................................................................................................473
ARP Learning via ARP Request................................................................................................................................... 473
Conguring ARP Retries............................................................................................................................................... 474
ICMP............................................................................................................................................................................... 475
Conguration Tasks for ICMP...................................................................................................................................... 475
Enabling ICMP Unreachable Messages...................................................................................................................... 475
ICMP Redirects..............................................................................................................................................................475
UDP Helper.....................................................................................................................................................................476
Congure UDP Helper.............................................................................................................................................476
Important Points to Remember..............................................................................................................................477
Enabling UDP Helper..................................................................................................................................................... 477
Conguring a Broadcast Address.................................................................................................................................477
Congurations Using UDP Helper................................................................................................................................478
UDP Helper with Broadcast-All Addresses.................................................................................................................478
UDP Helper with Subnet Broadcast Addresses.........................................................................................................479
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