Home » Dell Manuals » Hubs & Switches » Dell PowerConnect 8100 » Manual Viewer

Dell PowerConnect 8100 CLI Reference Guide - Page 359

DHCP Snooping Commands

View all Dell PowerConnect 8100 manuals

Add to My Manuals
Save this manual to your list of manuals

Page 359 highlights

12 DHCP Snooping Commands DHCP Snooping is a security feature that monitors DHCP messages between DHCP clients and DHCP server to filter harmful DHCP messages and build a bindings database of {MAC address, IP address, VLAN ID, interface} tuples that are considered authorized. The DHCP snooping application processes incoming DHCP messages. For DHCPRELEASE and DHCPDECLINE messages, the application compares the receive interface and VLAN with the client's interface and VLAN in the bindings database. If the interfaces do not match, the application logs the event and drops the message. For valid client messages, DHCP snooping compares the source MAC address to the DHCP client hardware address. When there is a mismatch, DHCP snooping logs and drops the packet. DHCP Snooping forwards valid client messages on trusted members within the VLAN. If DHCP Relay and/or DHCP Server coexist with DHCP Snooping, the DHCP client message is sent to the DHCP Relay or/and DHCP Server for further processing. The DHCP Snooping application uses DHCP messages to build and maintain the binding's database. The binding's database only includes data for clients on untrusted ports. DHCP Snooping creates a tentative binding from DHCP DISCOVER and REQUEST messages. Tentative bindings tie a client to a port (the port where the DHCP client message was received). Tentative bindings are completed when DHCP Snooping learns the client's IP address from a DHCP ACK message on a trusted port. DHCP Snooping removes bindings in response to DECLINE, RELEASE, and NACK messages. The DHCP Snooping application ignores the ACK messages as a reply to the DHCP Inform messages received on trusted ports. The network administrator can enter static bindings into the binding database. IP Source Guard and Dynamic ARP Inspection use the DHCP Snooping bindings database for the validation of IP and ARP packets. DHCP Snooping Commands 359

Section	Page
Command Groups	77
Introduction	77
Command Groups	77
Mode Types	81
Layer 2 Commands	83
AAA	83
Administrative Profiles	84
ACL	85
Address Table	86
Auto-VoIP	87
CDP Interoperability	87
DHCP L2 Relay	88
DHCP Management Interface	88
DHCP Snooping	89
Dynamic ARP Inspection	90
E-mail Alerting	91
Ethernet Configuration	92
Ethernet CFM	93
GVRP	94
IGMP Snooping	95
IGMP Snooping Querier	96
IP Addressing	96
IPv6 ACL	98
IPv6 MLD Snooping	98
IPv6 MLD Snooping Querier	99
IP Source Guard	99
iSCSI Optimization	100
Link Dependency	100
LLDP	101
Multicast VLAN Registration	102
Port Channel	102
Port Monitor	103
QoS	103
Radius	108
Spanning Tree	110
TACACS+	111
VLAN	112
802.1x	114
Data Center Technology Commands	117
Data Center Bridging Commands	117
FIP Snooping Commands	117
Priority Flow Control Commands	118
Layer 3 Commands	119
ARP (IPv4)	119
DHCP Server and Relay Agent (IPv4)	120
DHCPv6	121
DVMRP	122
IGMP	123
IGMP Proxy	124
IP Helper/DHCP Relay	125
IP Routing	126
IPv6 Routing	127
Loopback Interface	130
Multicast	130
IPv6 Multicast	132
OSPF	134
OSPFv3	138
Router Discovery Protocol	141
Routing Information Protocol	142
Tunnel Interface	143
Virtual Router Redundancy	144
Utility Commands	146
Auto-Install	146
Captive Portal	146
CLI Macro	149
Clock	149
Command Line Configuration Scripting	150
Denial of Service	151
Line	152
Management ACL	153
Mode	153
Password Management	153
PHY Diagnostics	155
RMON	155
SDM Templates	156
Serviceability Tracing	156
sFlow	158
SNMP	158
SSH	159
Syslog	160
System Management	161
Telnet Server	164
Terminal Length	164
Time Ranges	165
USB Flash Drive	165
User Interface	165
Web Server	166
Using the CLI	167
Introduction	167
Entering and Editing CLI Commands	167
History Buffer	168
Negating Commands	169
Show Command	169
Command Completion	170
Short Form Commands	170
Keyboard Shortcuts	170
Parameters	171
Operating on Multiple Objects (Range)	172
Command Scripting	173
CLI Command Notation Conventions	173
Interface Naming Conventions	174
Examples	176
CLI Command Modes	177
User EXEC Mode	178
Privileged EXEC Mode	178
Global Configuration Mode	179
Preconfiguration	179
Interface and Other Specific Configuration Modes	179
Identifying the Switch and Command Mode from the System Prompt	182
Navigating CLI Command Modes	182
Starting the CLI	190
Easy Setup Wizard	191
Using CLI Functions and Tools	198
Configuration Management	198
Management Interface Security	200
Management ACL	203
Other CLI Tools and Capabilities	204
Layer 2 Switching Commands	235
AAA Commands	237
TACACS+ Accounting	238
Accounting Method Lists	239
Access Line Modes	239
Commands in this Chapter	239
aaa authentication dot1x default	240
Syntax	240
Parameter Description	240
Default Configuration	240
Command Mode	241
User Guidelines	241
Example	241
aaa authentication enable	241
Syntax	241
Default Configuration	242
Command Mode	242
User Guidelines	242
Example	243
aaa authentication login	243
Syntax	243
Default Configuration	244
Command Mode	244
User Guidelines	244
Example	245
aaa authorization	245
Syntax	245
Parameter Description	245
Default Configuration	246
Command Mode	246
User Guidelines	247
aaa authorization network default radius	247
Syntax	247
Default Configuration	248
Command Mode	248
User Guidelines	248
Example	248
aaa ias-user username	248
Syntax	248
Parameter Description	248
Default Configuration	248
Command Mode	249
User Guidelines	249
Examples	249
aaa new-model	249
Syntax	249
Parameter Description	249
Default Configuration	249
Command Mode	249
User Guidelines	249
Example	250
clear (IAS)	250
Syntax	250
Parameter Description	250
Default Configuration	250
Command Mode	250
User Guidelines	250
Example	250
authorization	250
Syntax	251
Parameter Description	251
Default Configuration	251
Command Mode	251
User Guidelines	251
Examples	251
enable authentication	252
Syntax	252
Default Configuration	252
Command Mode	252
User Guidelines	252
Example	252
enable password	253
Syntax	253
Default Configuration	253
Command Mode	253
User Guidelines	253
Example	253
ip http authentication	254
Syntax	254
Default Configuration	254
Command Mode	254
User Guidelines	254
Example	254
ip https authentication	255
Syntax	255
Parameter Description	255
Default Configuration	255
Command Mode	255
User Guidelines	255
Example	256
login authentication	256
Syntax	256
Default Configuration	256
Command Mode	256
User Guidelines	256
Example	256
password (aaa IAS User Configuration)	257
Syntax	257
Parameter Description	257
Default Configuration	257
Command Mode	257
User Guidelines	257
Example	257
password (Line Configuration)	258
Syntax	258
Default Configuration	258
Command Mode	258
User Guidelines	258
Example	258
password (User EXEC)	259
Syntax	259
Parameter Description	259
Default Configuration	259
Command Mode	259
User Guidelines	259
Example	259
show aaa ias-users	260
Syntax	260
Parameter Description	260
Default Behavior	260
Command Mode	260
User Guidelines	260
Example	260
show aaa statistics	261
Syntax	261
Default Configuration	261
Command Mode	261
User Guidelines	261
Examples	261
show authentication methods	262
Syntax	262
Default Configuration	262
Command Mode	262
User Guidelines	262
Example	262
show authorization methods	263
Syntax	263
Default Configuration	263
Command Mode	263
User Guidelines	263
Example	263
show users accounts	264
Syntax	264
Parameter Description	264
Default Configuration	265
Command Mode	265
User Guidelines	265
Example	265
show users login-history	266
Syntax	266
Default Configuration	266
Command Mode	266
User Guidelines	266
Example	266
username	267
Syntax	267
Parameter Description	267
Default Configuration	268
Command Mode	268
User Guidelines	268
Example	269
username unlock	269
Syntax	270
Parameter Description	270
Default Configuration	270
Command Mode	270
User Guidelines	270
Administrative Profiles Commands	271
Overview	271
RADIUS and TACACS+	272
Commands in this Chapter	272
admin-profile	273
Syntax	273
Parameter Description	273
Default Configuration	273
Command Mode	273
User Guidelines	273
Example	273
description (Administrative Profile Config)	274
Syntax	274
Parameter Description	274
Default Configuration	274
Command Mode	274
User Guidelines	274
Example	274
rule	275
Syntax	275
Parameter Description	275
Default Configuration	275
Command Mode	275
User Guidelines	275
Example	275
show admin-profiles	276
Syntax	276
Parameter Description	276
Default Configuration	276
Command Mode	276
User Guidelines	276
Example	277
show admin-profiles brief	277
Syntax	277
Parameter Description	277
Default Configuration	277
Command Mode	277
User Guidelines	277
Example	278
show cli modes	278
Syntax	278
Default Configuration	278
Command Mode	278
User Guidelines	278
Example	278
ACL Commands	281
ACL Logging	281
How to Build ACLs	282
Commands in this Chapter	284
access-list	284
Parameter Description	285
Default Configuration	285
Command Mode	286
User Guidelines	286
Examples	286
deny \| permit (IP ACL)	286
Syntax	286
Parameter Description	287
Default Configuration	287
Command Mode	287
User Guidelines	287
deny \| permit (Mac-Access-List-Configuration)	288
Syntax	288
Parameter Description	289
Default Configuration	290
Command Mode	290
User Guidelines	290
Example	290
ip access-group	290
Syntax	290
Default Configuration	291
Command Mode	291
User Guidelines	291
Examples	291
mac access-group	291
Syntax	291
Default Configuration	292
Command Mode	292
User Guidelines	292
Example	292
mac access-list extended	292
Syntax	292
Default Configuration	293
Command Mode	293
User Guidelines	293
Example	293
mac access-list extended rename	293
Syntax	293
Default Configuration	293
Command Mode	294
User Guidelines	294
Example	294
service-acl input	294
Syntax	294
Parameter Description	294
Default Configuration	295
Command Mode	295
User Guidelines	295
show service-acl interface	295
Syntax	295
Parameter Description	295
Default Configuration	295
Command Mode	295
User Guidelines	295
Example	296
show ip access-lists	296
Syntax	296
Parameter Description	296
Examples	297
show mac access-list	297
Syntax	297
Parameter Description	297
Default Configuration	297
Command Mode	297
User Guidelines	297
Example	298
Address Table Commands	299
Commands in this Chapter	300
clear mac address-table	300
Syntax	300
Parameter Description	300
Default Configuration	301
Command Mode	301
User Guidelines	301
Example	301
mac address-table aging-time	301
Syntax	301
Parameter Description	301
Default Configuration	301
Command Mode	302
User Guidelines	302
Example	302
mac address-table multicast forbidden address	302
Syntax	302
Parameter Description	302
Default Configuration	303
Command Mode	303
User Guidelines	303
Examples	303
mac address-table static vlan	303
Syntax	303
Syntax Description	304
Default Configuration	304
Command Mode	304
User Guidelines	304
Example	304
port security	304
Syntax	305
Default Configuration	305
Command Mode	305
User Guidelines	305
Example	305
port security max	305
Syntax	305
Default Configuration	306
Command Mode	306
User Guidelines	306
Example	306
show mac address-table multicast	306
Syntax	306
Default Configuration	306
Command Mode	307
User Guidelines	307
Example	307
show mac address-table	307
Syntax	307
Parameter Description	308
Default Configuration	308
Command Mode	308
User Guidelines	308
Example	308
show mac address-table address	309
Syntax	309
Parameter Description	309
Default Configuration	309
Command Mode	309
User Guidelines	309
Example	309
show mac address-table count	310
Syntax	310
Parameter Description	310
Default Configuration	310
Command Mode	310
User Guidelines	310
Example	310
show mac address-table dynamic	311
Syntax	311
Parameter Description	311
Default Configuration	311
Command Mode	311
User Guidelines	311
Example	311
show mac address-table interface	312
Syntax	312
Parameter Description	312
Default Configuration	312
Command Mode	312
User Guidelines	312
Example	313
show mac address-table static	313
Syntax	313
Parameter Description	313
Default Configuration	314
Command Mode	314
User Guidelines	314
Example	314
show mac address-table vlan	314
Syntax	314
Parameter Description	314
Default Configuration	315
Command Mode	315
User Guidelines	315
Example	315
show ports security	315
Syntax	316
Default Configuration	316