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ip dhcp snooping server-screen

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DGS-3630 Layer 3 Stackable Managed Switch CLI Reference Guide Example This example shows how to enter the DHCP server screen configure mode to define the profile "campus". Switch# configure terminal Switch(config)# service dhcp Switch(config)# dhcp-server-screen profile campus Switch(config-dhcp-server-screen)# 26-4 ip dhcp snooping server-screen This command is used to enable DHCP server screening. Use the no form of this command to disable it. ip dhcp snooping server-screen [SERVER-IP-ADDRESS profile PROFILE-NAME] no ip dhcp snooping server-screen [SERVER-IP-ADDRESS] Parameters SERVER-IP-ADDRESS profile PROFILE-NAME (Optional) Specifies the trust DHCP sever IP address. (Optional) Specifies the profile with the client MAC address list for the DHCP sever. Default None. Command Mode Interface Configuration Mode. Command Default Level Level: 12. Usage Guideline The command is available for physical port and port channel. The DHCP server screening function is used to filter the DHCP server packets on the specific interface and receive the trust packets from the specific source. This feature can make a protected network usable when a malicious host sends DHCP server packets. If the server IP address is not specified, it will enabled or disabled the DHCP server screen on the interface. By default, the DHCP server screen is disabled on all interfaces. If enabled, the DHCP server screen, on a specific interface, will filter all DHCP server packets from the interface and only forward trusted server packets. If a server screen entry is defined with a profile that contains a client MAC address, the server message with the server IP address and the client addresses contained in the profile is forwarded. If an entry is defined without the client's MAC address, the server message with the specified server IP address will be forwarded. Each server can only have one corresponding entry in the table. If the entry is defined with a profile but the entry does not exist, messages with the server IP specified by the entry are not forwarded. 460

Section	Page
Table of Contents	2
1. Introduction	6
Audience	6
Other Documentation	6
Conventions	6
Notes, Notices, and Cautions	6
Command Descriptions	7
Command Modes	7
User EXEC Mode at Basic User Level	8
Privileged EXEC Mode at Advanced User Level	8
Privileged EXEC Mode at Power User Level	8
Privileged EXEC Mode at Operator Level	9
Privileged EXEC Mode at Administrator Level	9
Global Configuration Mode	9
Interface Configuration Mode	9
Creating a User Account	9
Interface Notation	10
Error Messages	11
Editing Features	11
Display Result Output Modifiers	12
2. Basic CLI Commands	14
2-1 help	14
Parameters	14
Default	14
Command Mode	14
Command Default Level	14
Usage Guideline	14
Example	14
2-2 enable	15
Parameters	15
Default	15
Command Mode	16
Command Default Level	16
Usage Guideline	16
Example	16
2-3 disable	16
Parameters	16
Default	16
Command Mode	16
Command Default Level	16
Usage Guideline	16
Example	17
2-4 configure terminal	17
Parameters	17
Default	17
Command Mode	17
Command Default Level	17
Usage Guideline	17
Example	17
2-5 login (EXEC)	17
Parameters	17
Default	18
Command Mode	18
Command Default Level	18
Usage Guideline	18
Example	18
2-6 login (Line)	18
Parameters	18
Default	18
Command Mode	18
Command Default Level	18
Usage Guideline	19
Example	19
2-7 logout	20
Parameters	20
Default	20
Command Mode	20
Command Default Level	20
Usage Guideline	20
Example	20
2-8 end	20
Parameters	20
Default	20
Command Mode	20
Command Default Level	21
Usage Guideline	21
Example	21
2-9 exit	21
Parameters	21
Default	21
Command Mode	21
Command Default Level	21
Usage Guideline	21
Example	21
2-10 show history	22
Parameters	22
Default	22
Command Mode	22
Command Default Level	22
Usage Guideline	22
Example	22
2-11 password-recovery	22
Parameters	22
Default	23
Command Mode	23
Command Default Level	23
Usage Guideline	23
Example	23
2-12 show environment	23
Parameters	23
Default	24
Command Mode	24
Command Default Level	24
Usage Guideline	24
Example	24
Display Parameters	24
2-13 show unit	24
Parameters	25
Default	25
Command Mode	25
Command Default Level	25
Usage Guideline	25
Example	25
2-14 show cpu utilization	25
Parameters	25
Default	26
Command Mode	26
Command Default Level	26
Usage Guideline	26
Example	26
2-15 show version	26
Parameters	27
Default	27
Command Mode	27
Command Default Level	27
Usage Guideline	27
Example	27
2-16 snmp-server enable traps environment	27
Parameters	27
Default	28
Command Mode	28
Command Default Level	28
Usage Guideline	28
Example	28
2-17 environment temperature threshold	28
Parameters	28
Default	28
Command Mode	28
Command Default Level	28
Usage Guideline	29
Example	29
2-18 show memory utilization	29
Parameters	29
Default	29
Command Mode	29
Command Default Level	29
Usage Guideline	29
Example	30
2-19 console-usb-timeout	30
Parameters	30
Default	30
Command Mode	30
Command Default Level	30
Usage Guideline	30
Example	31
2-20 console-usb	31
Parameters	31
Default	31
Command Mode	31
Command Default Level	31
Usage Guideline	31
Example	31
2-21 privilege	31
Parameters	32
Default	32
Command Mode	32
Command Default Level	32
Usage Guideline	32
Example	32
2-22 show privilege	32
Parameters	32
Default	32
Command Mode	32
Command Default Level	32
Usage Guideline	33
Example	33
3. 802.1X Commands	34
3-1 clear dot1x counters	34
Parameters	34
Default	34
Command Mode	34
Command Default Level	34
Usage Guideline	34
Example	34
3-2 dot1x control-direction	34
Parameters	34
Default	35
Command Mode	35
Command Default Level	35
Usage Guideline	35
Example	35
3-3 dot1x default	35
Parameters	35
Default	35
Command Mode	36
Command Default Level	36
Usage Guideline	36
Example	36
3-4 dot1x port-control	36
Parameters	36
Default	36
Command Mode	36
Command Default Level	36
Usage Guideline	36
Example	37
3-5 dot1x forward-pdu	37
Parameters	37
Default	37
Command Mode	37
Command Default Level	37
Usage Guideline	37
Example	37
3-6 dot1x initialize	37
Parameters	38
Default	38
Command Mode	38
Command Default Level	38
Usage Guideline	38
Example	38
3-7 dot1x max-req	38
Parameters	38
Default	38
Command Mode	39
Command Default Level	39
Usage Guideline	39
Example	39
3-8 dot1x pae authenticator	39
Parameters	39
Default	39
Command Mode	39
Command Default Level	39
Usage Guideline	39
Example	40
3-9 dot1x re-authenticate	40
Parameters	40
Default	40
Command Mode	40
Command Default Level	40
Usage Guideline	40
Example	41
3-10 dot1x system-auth-control	41
Parameters	41
Default	41
Command Mode	41
Command Default Level	41
Usage Guideline	41
Example	41
3-11 dot1x timeout	41
Parameters	42
Default	42
Command Mode	42
Command Default Level	42
Usage Guideline	42
Example	42
3-12 show dot1x	42
Parameters	42
Default	43
Command Mode	43
Command Default Level	43
Usage Guideline	43
Example	43
3-13 show dot1x diagnostics	43
Parameters	44
Default	44
Command Mode	44
Command Default Level	44
Usage Guideline	44
Example	44
3-14 show dot1x statistics	45
Parameters	45
Default	45
Command Mode	45
Command Default Level	45
Usage Guideline	45
Example	45
3-15 show dot1x session-statistics	46
Parameters	46
Default	46
Command Mode	46
Command Default Level	46
Usage Guideline	46
Example	46
3-16 snmp-server enable traps dot1x	46
Parameters	47
Default	47
Command Mode	47
Command Default Level	47
Usage Guideline	47
Example	47
4. Access Control List (ACL) Commands	48
4-1 access-list resequence	48
Parameters	48
Default	48
Command Mode	48
Command Default Level	48
Usage Guideline	48
Example	49
4-2 acl-hardware-counter	49
Parameters	49
Default	50
Command Mode	50
Command Default Level	50
Usage Guideline	50
Example	50
4-3 action	50
Parameters	50
Default	50
Command Mode	50
Command Default Level	50
Usage Guideline	51
Example	51
4-4 clear acl-hardware-counter	51
Parameters	51
Default	51
Command Mode	51
Command Default Level	51
Usage Guideline	52
Example	52
4-5 expert access-group	52
Parameters	52
Default	52
Command Mode	52
Command Default Level	52
Usage Guideline	52
Example	53
4-6 expert access-list	53
Parameters	53
Default	53
Command Mode	53
Command Default Level	53
Usage Guideline	53
Example	53
4-7 ip access-group	54
Parameters	54
Default	54
Command Mode	54
Command Default Level	54
Usage Guideline	54
Example	54
4-8 ip access-list	54
Parameters	55
Default	55
Command Mode	55
Command Default Level	55
Usage Guideline	55
Example	55
4-9 ipv6 access-group	55
Parameters	56
Default	56
Command Mode	56
Command Default Level	56
Usage Guideline	56
Example	56
4-10 ipv6 access-list	56
Parameters	56
Default	57
Command Mode	57
Command Default Level	57
Usage Guideline	57
Example	57
4-11 list-remark	57
Parameters	57
Default	57
Command Mode	58
Command Default Level	58
Usage Guideline	58
Example	58
4-12 mac access-group	58
Parameters	58
Default	58
Command Mode	58
Command Default Level	59
Usage Guideline	59
Example	59
4-13 mac access-list	59
Parameters	59
Default	59
Command Mode	59
Command Default Level	59
Usage Guideline	59
Example	60
4-14 match ip address	60
Parameters	60
Default	60
Command Mode	60
Command Default Level	60
Usage Guideline	60
Example	61
4-15 match ipv6 address	61
Parameters	61
Default	61
Command Mode	61
Command Default Level	61
Usage Guideline	61
Example	62
4-16 match mac address	62
Parameters	62
Default	62
Command Mode	62
Command Default Level	62
Usage Guideline	62
Example	63
4-17 permit \| deny \| deny-cpu (expert access-list)	63
Parameters	63
Default	65
Command Mode	65
Command Default Level	65
Usage Guideline	65
Example	66
4-18 permit \| deny \| deny-cpu (ip access-list)	66
Parameters	66
Default	68
Command Mode	68
Command Default Level	68
Usage Guideline	68
Example	68
4-19 permit \| deny \| deny-cpu (ipv6 access-list)	69
Parameters	69
Default	70
Command Mode	70
Command Default Level	70
Usage Guideline	71
Example	71
4-20 permit \| deny \| deny-cpu (mac access-list)	71
Parameters	71
Default	72
Command Mode	72
Command Default Level	72
Usage Guideline	72
Example	73
4-21 show access-group	73
Parameters	73
Default	73
Command Mode	73
Command Default Level	73
Usage Guideline	73
Example	73
4-22 show access-list	73
Parameters	74
Default	74
Command Mode	74
Command Default Level	74
Usage Guideline	74
Example	74
4-23 show vlan access-map	75
Parameters	75
Default	75
Command Mode	75
Command Default Level	75
Usage Guideline	75
Example	76
4-24 show vlan filter	76
Parameters	76
Default	76
Command Mode	76
Command Default Level	76
Usage Guideline	77
Example	77
4-25 vlan access-map	77
Parameters	77
Default	77
Command Mode	77
Command Default Level	77
Usage Guideline	77
Example	78
4-26 vlan filter	78
Parameters	78
Default	78
Command Mode	78
Command Default Level	78
Usage Guideline	78
Example	78
5. Access Management Commands	79
5-1 access class	79
Parameters	79
Default	79
Command Mode	79
Command Default Level	79
Usage Guideline	79
Example	79
5-2 banner login	79
Parameters	80
Default	80
Command Mode	80
Command Default Level	80
Usage Guideline	80
Example	80
5-3 do	80
Parameters	81
Default	81
Command Mode	81
Command Default Level	81
Usage Guideline	81
Example	81
5-4 prompt	81
Parameters	81
Default	81
Command Mode	82
Command Default Level	82
Usage Guideline	82

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1,232
1,233
1,234
1,235
1,236
1,237
1,238
1,239
1,240
1,241
1,242
1,243
1,244
1,245
1,246
1,247
1,248
1,249
1,250
1,251
1,252
1,253
1,254
1,255
1,256
1,257
1,258
1,259
1,260
1,261
1,262
1,263
1,264
1,265
1,266
1,267
1,268
1,269
1,270
1,271
1,272
1,273
1,274
1,275
1,276
1,277
1,278
1,279
1,280
1,281
1,282
1,283
1,284
1,285
1,286
1,287
1,288
1,289
1,290
1,291
1,292
1,293
1,294
1,295
1,296
1,297
1,298
1,299
1,300
1,301
1,302
1,303
1,304
1,305
1,306
1,307
1,308
1,309
1,310
1,311
1,312
1,313
1,314
1,315
1,316
1,317
1,318
1,319
1,320
1,321
1,322
1,323
1,324
1,325
1,326
1,327
1,328
1,329
1,330
1,331
1,332
1,333
1,334
1,335
1,336
1,337
1,338
1,339
1,340
1,341
1,342
1,343
1,344
1,345
1,346
1,347
1,348
1,349
1,350
1,351
1,352
1,353
1,354
1,355
1,356
1,357
1,358
1,359
1,360
1,361
1,362
1,363
1,364
1,365
1,366
1,367
1,368
1,369
1,370
1,371
1,372
1,373
1,374
1,375
1,376
1,377
1,378
1,379
1,380
1,381
1,382
1,383
1,384
1,385
1,386
1,387
1,388
1,389
1,390
1,391
1,392
1,393
1,394
1,395
1,396
1,397
1,398
1,399
1,400
1,401
1,402
1,403
1,404
1,405
1,406
1,407
1,408
1,409
1,410
1,411
1,412
1,413
1,414
1,415
1,416
1,417
1,418
1,419
1,420
1,421
1,422
1,423
1,424
1,425
1,426
1,427
1,428
1,429
1,430
1,431
1,432
1,433
1,434
1,435
1,436
1,437
1,438
1,439
1,440
1,441
1,442
1,443
1,444
1,445
1,446
1,447
1,448
1,449
1,450
1,451
1,452
1,453
1,454
1,455
1,456
1,457
1,458
1,459
1,460
1,461
1,462
1,463
1,464
1,465
1,466
1,467
1,468
1,469
1,470
1,471
1,472
1,473
1,474
1,475
1,476
1,477
1,478
1,479
1,480
1,481
1,482
1,483
1,484
1,485
1,486
1,487
1,488
1,489
1,490
1,491
1,492
1,493
1,494
1,495
1,496
1,497
1,498
1,499
1,500
1,501
1,502
1,503
1,504
1,505
1,506
1,507
1,508
1,509
1,510
1,511
1,512
1,513
1,514
1,515
1,516
1,517
1,518
1,519
1,520
1,521
1,522
1,523
1,524
1,525
1,526
1,527
1,528
1,529
1,530
1,531
1,532
1,533
1,534
1,535
1,536
1,537
1,538
1,539
1,540
1,541
1,542
1,543
1,544
1,545
1,546
1,547
1,548
1,549
1,550
1,551
1,552
1,553
1,554
1,555
1,556
1,557
1,558
1,559
1,560
1,561
1,562
1,563
1,564
1,565
1,566
1,567
1,568
1,569
1,570
1,571
1,572
1,573
1,574
1,575
1,576
1,577
1,578
1,579
1,580
1,581
1,582
1,583
1,584
1,585
1,586
1,587
1,588
1,589
1,590
1,591
1,592
1,593
1,594
1,595
1,596
1,597
1,598
1,599
1,600
1,601
1,602
1,603
1,604
1,605
1,606
1,607
1,608
1,609
1,610
1,611
1,612
1,613
1,614
1,615
1,616
1,617
1,618
1,619
1,620
1,621
1,622
1,623
1,624
1,625
1,626
1,627
1,628
1,629
1,630
1,631
1,632
1,633
1,634
1,635
1,636
1,637
1,638
1,639
1,640
1,641
1,642
1,643
1,644
1,645
1,646
1,647
1,648
1,649
1,650
1,651
1,652
1,653
1,654
1,655
1,656
1,657
1,658
1,659
1,660
1,661
1,662
1,663
1,664
1,665
1,666
1,667
1,668
1,669
1,670
1,671
1,672
1,673
1,674
1,675
1,676
1,677
1,678
1,679
1,680
1,681
1,682
1,683
1,684
1,685
1,686
1,687
1,688
1,689
1,690
1,691
1,692
1,693
1,694
1,695
1,696
1,697
1,698
1,699
1,700
1,701
1,702
1,703
1,704
1,705
1,706
1,707
1,708
1,709
1,710
1,711
1,712
1,713
1,714
1,715
1,716
1,717
1,718
1,719
1,720
1,721
1,722
1,723
1,724
1,725
1,726
1,727
1,728
1,729
1,730
1,731
1,732
1,733
1,734
1,735
1,736
1,737
1,738
1,739
1,740
1,741
1,742
1,743
1,744
1,745
1,746
1,747
1,748
1,749
1,750
1,751
1,752
1,753
1,754
1,755
1,756
1,757
1,758
1,759
1,760
1,761
1,762
1,763
1,764
1,765
1,766
1,767
1,768

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DGS-3630 Layer 3 Stackable Managed Switch CLI Reference Guide

460

Example

This example shows how to enter the DHCP server screen configure mode to define the profile “campus”.

Switch# configure terminal

Switch(config)# service dhcp

Switch(config)# dhcp-server-screen profile campus

Switch(config-dhcp-server-screen)#

26-4

ip dhcp snooping server-screen

This command is used to enable DHCP server screening. Use the

form of this command to disable it.

ip dhcp snooping server-screen [

SERVER-IP-ADDRESS

profile

PROFILE-NAME

]

no ip dhcp snooping server-screen [

SERVER-IP-ADDRESS

]

Parameters

SERVER-IP-ADDRESS

(Optional) Specifies the trust DHCP sever IP address.

profile

PROFILE-NAME

(Optional) Specifies the profile with the client MAC address list for the DHCP

sever.

Default

None.

Command Mode

Interface Configuration Mode.

Command Default Level

Level: 12.

Usage Guideline

The command is available for physical port and port channel.

The DHCP server screening function is used to filter the DHCP server packets on the specific interface and receive

the trust packets from the specific source. This feature can make a protected network usable when a malicious

host sends DHCP server packets.

If the server IP address is not specified, it will enabled or disabled the DHCP server screen on the interface. By

default, the DHCP server screen is disabled on all interfaces. If enabled, the DHCP server screen, on a specific

interface, will filter all DHCP server packets from the interface and only forward trusted server packets.

If a server screen entry is defined with a profile that contains a client MAC address, the server message with the

server IP address and the client addresses contained in the profile is forwarded.

If an entry is defined without the client’s MAC address, the server message with the specified server IP address will

be forwarded. Each server can only have one corresponding entry in the table.

If the entry is defined with a profile but the entry does not exist, messages with the server IP specified by the entry

are not forwarded.