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Dell PowerSwitch S4128F-ON EMC SmartFabric OS10 User Guide Release 10.5.0 - Page 206

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• User actions, such as DHCP clear or disabling DHCP snooping You can add a static DHCP snooping binding entry using the CLI. If you add a static entry for a client, any dynamic entry that is present for the same client is overwritten. The switch does not remove static entries if it receives DHCP RELEASE or DHCP DECLINE packets. By default, DHCP snooping is disabled globally and enabled on VLANs. For the DHCP snooping feature to work, enable it globally. NOTE: If you move a DHCP client from an untrusted interface to another untrusted interface within the VLAN, the DHCP snooping binding database is not updated. The switch drops subsequent packets from the client. However, if you move a DHCP client from an untrusted interface to a trusted interface, there is no impact to the traffic from the client. Restrictions for DHCP snooping • The management VLAN does not support DHCP snooping. • VxLAN bridges do not support DHCP snooping. • The maximum number of supported DHCP snooping binding entries is 4000. • OS10 does not support multi-hop DHCP snooping. • For the DHCP snooping functionality to work correctly, ensure that the DHCP server supports option 82 (RFC 3046). • Enable option 82 (RFC 3046) on the DHCP server for the DHCP Snooping functionality to work correctly. Rogue DHCP server detection In the following topology, a trusted DHCP server, a DHCP client, and a rogue DHCP server are connected to the DHCP snooping switch. The DHCP client and DHCP server are on the same VLAN. The physical interface eth 1/1/2 is a trusted interface. When the rogue DHCP server sends a DHCP packet to the client, the switch analyzes the packet. As the rogue server is connected to the switch to an untrusted eth 1/1/3 interface the switch deems the server as a rogue DHCP server and drops the packet. DHCP snooping with DHCP relay In the following topology, the DHCP snooping switch is the DHCP relay agent for DHCP clients on VLAN 100. The DHCP server is reachable on VLAN 200 through eth 1/1/2. The switch forwards the client DHCP messages to the trusted DHCP server. The switch processes DHCP packets from the DHCP server before forwarding them to DHCP clients. As the rogue server is connected to the switch to the eth 1/1/3 interface which is untrusted, the switch drops DHCP packets from that interface. 206 System management

Section	Page
Dell EMC SmartFabric OS10 User Guide Release 10.5.0	3
Change history	28
Getting Started with Dell EMC SmartFabric OS10	31
Switch with factory-installed OS10	32
Log in	32
Check OS10 version	33
OS10 upgrade	33
Download OS10 image for upgrade	33
Install OS10 upgrade	33
Install OS10 upgrade	35
Install firmware upgrade	37
Upgrade commands	37
boot system	37
image cancel	37
image copy	38
image download	38
image install	38
show boot	39
show image firmware	40
show image status	40
show version	41
Check OS10 license	41
Re-install license	42
Switch without OS installed	42
Uninstall existing OS	43
Download OS10 image	43
Installation using ONIE	44
Automatic installation	44
Manual installation	46
Log in	46
Install OS10 license	47
Switch deployment options	49
Manual CLI configuration	49
ZTD-automated switch deployment	50
Ansible-automated switch provisioning	50
MX7000 Feb 2020 Solution Update Instructions	50
Remote access	57
Configure Management IP address	57
Configure Management route	58
Configure username and password	58
CLI Basics	60
CONFIGURATION mode	61
Check device status	61
Related Videos	63
Command help	63
Candidate configuration	64
Copy running configuration	66
Restore startup configuration	66
Reload system image	67
Filter show commands	67
Common OS10 commands	68
boot	68
commit	68
configure	68
copy	69
delete	70
dir	71
discard	72
do	72
end	72
exit	73
hostname	73
license	74
lock	74
management route	74
move	75
no	75
ping	76
ping6	77
reload	79
show boot	79
show candidate-configuration	80
show environment	82
show inventory	83
show ip management-route	83
show ipv6 management-route	84
show license status	84
show running-configuration	85
show startup-configuration	87
show system	88
show version	90
start	90
system	91
system-cli disable	91
system-user linuxadmin disable	92
system identifier	92
terminal	92
traceroute	93
unlock	94
username password role	94
write	95
Advanced CLI tasks	96
Command alias	96
Multi-line alias	97
alias	99
alias (multi-line)	100
default (alias)	101
description (alias)	101
line (alias)	101
show alias	102
Batch mode	103
batch	103
Linux shell commands	104
Using OS9 commands	106
feature config-os9-style	106
Dell EMC SmartFabric OS10 zero-touch deployment	107
ZTD DHCP server configuration	109
ZTD provisioning script	109
ZTD CLI batch file	110
Post-ZTD script	110
ZTD commands	111
reload ztd	111
show ztd-status	111
ztd cancel	112
Dell EMC SmartFabric OS10 provisioning	113
Using Ansible	113
Example: Configure an OS10 switch using Ansible	114
SmartFabric Services	117
SmartFabric Services personalities	117
SmartFabric Services for leaf and spine	117
SmartFabric Services for PowerEdge MX	118
SmartFabric Services for leaf and spine	119
SmartFabric Services Components	120
SmartFabric Services logical entities	121
Uplinks	122
Uplink bonding options	123
Spanning tree considerations	123
Dynamic onboarding for integrated devices	123
Statically onboarded server	123
Static onboarding for nonintegrated devices	124
Backup and Restore of fabric state	124
Enable SmartFabric Services on the switches	124
Enable SmartFabric Services using GUI	125
SmartFabric Services Graphical User Interface	125
Configure SmartFabric Services initial setup	126
Update Default Fabric, Switch Names, and Descriptions wizard	127
Create Uplink for External Network Connectivity wizard	127
Configure Layer 2 uplink	127
Configure Layer 3 VLAN uplink	127
Configure Layer 3 Routed uplink	128
Breakout Switch Ports wizard	128
Configure Jump Host wizard	129
Update Network Configuration wizard	129
Onboard a Server onto the Fabric wizard	129
Edit Default Fabric Settings wizard	129
Restore wizard	130
Fabric operations and life cycle management	130
Configuring FEC using MSM	130
SFS Support for MSTP on Layer3 fabric	130
SmartFabric commands	131
smartfabric l3fabric enable	131
smartfabric vlti	132
show smartfabric cluster	132
show smartfabric cluster member	133
show smartfabric details	134
show smartfabric networks	135
show smartfabric nodes	135
show smartfabric personality	136
show smartfabric uplinks	137
show smartfabric validation-errors	138
show smartfabric discovered-server	139
show smartfabric discovered-server discovered-server-interface	140
show smartfabric configured-server	140
show smartfabric configured-server configured-server-interface	141
SmartFabric Director	143
Enable SmartFabric Director mode on a switch	143
Support for SmartFabric Director	143
gRPC Network Management Interface agent	143
Lifecycle Management using SmartFabric Director	146
SmartFabric Director commands	147
switch-operating-mode	147
gnmi-security-profile	147
show switch-operating-mode	148
show sfd status	148
System management	149
System banners	149
Login banner	149
Message of the day banner	150
System banner commands	150
banner login	150
banner motd	151
User session management	151
User session management commands	152
exec-timeout	152
kill-session	152
show sessions	152
Telnet server	153
Telnet commands	153
ip telnet server enable	153
ip telnet server vrf	154
Simple Network Management Protocol	154
SNMP security models and levels	154
MIBs	155
SNMPv3	156
SNMP engine ID	156
SNMP groups and users	156
SNMP views	156
Configure SNMP	156
Configure SNMP engine ID	157
Configure SNMP views	157
Configure SNMP groups	157
Configure SNMP users	158
Generate SNMPv3 localized keys	159
Configure SNMP traps	159
Configure SNMP informs	160
SNMP commands	160
show snmp community	160
show snmp engineID	161
show snmp group	161
show snmp user	161
show snmp view	162
snmp-server community	162
snmp-server contact	163
snmp-server enable traps	163
snmp-server engineID	164
snmp-server group	164
snmp-server host	165
snmp-server location	166
snmp-server user	167
snmp-server view	168
snmp-server vrf	168
Example: Configure SNMP	169
System clock	169
Time zones and UTC offset reference	170
System Clock commands	187
clock set	187
clock timezone	187
show clock	188
show clock timezone	188
Network Time Protocol	189
Enable NTP	189
Broadcasts	190
Source IP address	190
Authentication	191
Sample NTP configuration	192
NTP commands	194
ntp authenticate	194
ntp authentication-key	195
ntp broadcast client	195
ntp disable	195
ntp enable vrf	196
ntp master	196
ntp server	196
ntp source	197
ntp trusted-key	197
show ntp associations	198
show ntp status	198
Dynamic Host Configuration Protocol	199
Packet format and options	200
DHCP server	201
Automatic address allocation	201
Hostname resolution	202
Manual binding entries	203
View DHCP Information	204
DHCP relay agent	205
Option 82 for security	205
DHCP snooping	205
DHCP snooping examples	209
DHCP snooping switch as a relay agent	211
DHCP snooping in a Layer 2 VLT setup	212
DHCP snooping with DHCP relay agent in a VLT setup	215
Dynamic ARP inspection	218
Source Address Validation	220
System domain name and list	221
DHCP commands	222
DHCP relay commands	222
ip helper-address	222
ipv6 helper-address	222
DHCP server commands	223
default-router address	223
disable	223
domain-name	224
dns-server address	224
hardware-address	224
host	224
ip dhcp server	225
lease	225
netbios-name-server address	225
netbios-node-type	226
network	226
pool	226
range	227
show ip dhcp binding	227
DHCP snooping commands	227
arp inspection	227
arp inspection-trust	228
arp inspection violation logging	228
clear ip arp inspection statistics	228
clear ip dhcp snooping binding	229
ip dhcp snooping (global)	229
ip dhcp snooping (interface)	230
ip dhcp snooping binding	230
ip dhcp snooping trust	230
ip dhcp snooping verify mac-address	231
show ip arp inspection database	231
show ip arp inspection statistics	232
show ip arp inspection logging	232
show ip dhcp snooping binding	232
DNS commands	233
ip domain-list	233
ip domain-name	233
ip host	233
ip name-server	234
show hosts	234
Interfaces	236
Ethernet interfaces	236
Unified port groups	236
Z9264F-ON port-group profiles	238
Port-groups on S5200F-ON switches	239
L2 mode configuration	246
L3 mode configuration	247
Fibre Channel interfaces	247
Configuring wavelength	249
Management interface	250
Management interface	250
VLAN interfaces	250
User-configured default VLAN	251
VLAN scale profile	251
Loopback interfaces	252
Port-channel interfaces	252
Create port-channel	253
Add port member	253
Minimum links	254
Assign Port Channel IP Address	254
Remove or disable port-channel	254
Load balance traffic	255
Change hash algorithm	255
Configure interface ranges	255
Switch-port profiles	256
S4148-ON Series port profiles	257
S4148U-ON port profiles	258
Configure negotiation modes on interfaces	259
Configure breakout mode	260
Breakout auto-configuration	261
Reset default configuration	262
Forward error correction	263
Energy-efficient Ethernet	264
Enable energy-efficient Ethernet	264
Clear EEE counters	265
View EEE status/statistics	265
EEE commands	266
clear counters interface eee	266
clear counters interface ethernet eee	266
eee	266
show interface eee	267
show interface eee statistics	267
show interface ethernet eee	267
show interface ethernet eee statistics	268
View interface configuration	268
Digital optical monitoring	271
Enable DOM and DOM traps	272
Default MTU Configuration	273
Interface commands	274
channel-group	274
default interface	274
default vlan-id	276
description (Interface)	277
duplex	278
enable dom	278
enable dom traps	278
feature auto-breakout	279
fec	279
interface breakout	280
interface ethernet	280
interface loopback	280
interface mgmt	281
interface null	281
interface port-channel	281
interface range	282
interface vlan	282
link-bundle-utilization	283
mode	283
mode l3	284
mtu	284
negotiation	285
port mode Eth	286
port-group	287
profile	287
scale-profile vlan	288
show discovered-expanders	288
show interface	289
show interface transceiver “Tunable wavelength”	290
show inventory media	291
show link-bundle-utilization	292
show port-channel summary	292
show port-group	293
show switch-port-profile	294
show system	294
show unit-provision	295
show vlan	296
shutdown	296
speed (Fibre Channel)	296
speed (Management)	297
switch-port-profile	297
switchport access vlan	299
switchport mode	299
switchport trunk allowed vlan	300
unit-provision	300
wavelength	301
default mtu	301
show default mtu	302
PowerEdge MX Ethernet I/O modules	303
Operating modes	303
Changing operating modes	305
Restrictions	305
Port groups on I/O modules	305
Double-density QSFP28 interfaces	305
Virtual ports	307
Single-density QSFP28 interfaces	310
Server-facing interfaces	312
Replace MX Ethernet I/O modules	313
Deployment instructions	313
Replace an IOM in Full-Switch VLT	313
Replace an IOM in SmartFabric	313
Remove and replace the faulty IOM	314
Verify and configure IOM settings	314
Identify the master IOM	314
Log in to the master IOM from the member	315
Initiate the module replacement workflow	316
Connect the new IOM	316
View SmartFabric Services configuration	316
Fibre Channel	317
Fibre Channel over Ethernet	318
Configure FIP snooping	318
Terminology	320
Virtual fabric	320
Fibre Channel zoning	322
F_Port on Ethernet	324
Pinning FCoE traffic to a specific port of a port-channel	324
Sample FSB configuration on VLT network	326
Sample FC Switch configuration on VLT network	328
Sample FSB configuration on non-VLT network	330
Sample FC Switch configuration on non-VLT network	332
Multi-hop FIP-snooping bridge	333
Configuration notes	333
Configure multi-hop FSB	334
Verify multi-hop FSB configuration	340
Sample Multi-hop FSB configuration	341
Configuration guidelines	354
NPIV Proxy Gateway cascading	354
Support for untagged VLAN in FCoE	357
Rebalance FC sessions (NPG)	357
Load balancing after system reboot	357
NPG rebalance topology	357
NPG switch configurations	358
Example: Manual rebalance trigger	360
Equivalent RESTCONF request for the rebalancing CLIs	362
F_Port commands	362
fc alias	362
fc zone	363
fc zoneset	363
feature fc	363
member (alias)	364
member (zone)	364
member (zoneset)	365
show fc alias	365
show fc interface-area-id mapping	365
show fc ns switch	366
show fc zone	366
show fc zoneset	367
zone default-zone permit	368
zoneset activate	368
NPG commands	369
fc port-mode F	369
feature fc npg	369
show npg devices	370
F_Port and NPG commands	370
clear fc statistics	370
fcoe	371
fcoe delay fcf-adv	371
name	371
Re-balance the FC sessions	372
show npg uplink-interface	374
show npg node-interface	375
show fc statistics	376
show fc switch	377
show running-config vfabric	377
show vfabric	378
vfabric	378
vfabric (interface)	379
vlan	379
FIP-snooping commands	379
feature fip-snooping	380
fip-snooping enable	380
fip-snooping fc-map	380
fip-snooping port-mode	381
FCoE commands	381
clear fcoe database	381
clear fcoe statistics	382
fcoe-pinned-port	382
fcoe max-sessions-per-enodemac	382
fcoe priority-bits	383
lldp tlv-select dcbxp-appln fcoe	383
show fcoe enode	384
show fcoe fcf	384
show fcoe pinned-port	385
show fcoe sessions	385
show fcoe statistics	386
show fcoe system	386
show fcoe vlan	387

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1,014
1,015
1,016
1,017
1,018
1,019
1,020
1,021
1,022
1,023
1,024
1,025
1,026
1,027
1,028
1,029
1,030
1,031
1,032
1,033
1,034
1,035
1,036
1,037
1,038
1,039
1,040
1,041
1,042
1,043
1,044
1,045
1,046
1,047
1,048
1,049
1,050
1,051
1,052
1,053
1,054
1,055
1,056
1,057
1,058
1,059
1,060
1,061
1,062
1,063
1,064
1,065
1,066
1,067
1,068
1,069
1,070
1,071
1,072
1,073
1,074
1,075
1,076
1,077
1,078
1,079
1,080
1,081
1,082
1,083
1,084
1,085
1,086
1,087
1,088
1,089
1,090
1,091
1,092
1,093
1,094
1,095
1,096
1,097
1,098
1,099
1,100
1,101
1,102
1,103
1,104
1,105
1,106
1,107
1,108
1,109
1,110
1,111
1,112
1,113
1,114
1,115
1,116
1,117
1,118
1,119
1,120
1,121
1,122
1,123
1,124
1,125
1,126
1,127
1,128
1,129
1,130
1,131
1,132
1,133
1,134
1,135
1,136
1,137
1,138
1,139
1,140
1,141
1,142
1,143
1,144
1,145
1,146
1,147
1,148
1,149
1,150
1,151
1,152
1,153
1,154
1,155
1,156
1,157
1,158
1,159
1,160
1,161
1,162
1,163
1,164
1,165
1,166
1,167
1,168
1,169
1,170
1,171
1,172
1,173
1,174
1,175
1,176
1,177
1,178
1,179
1,180
1,181
1,182
1,183
1,184
1,185
1,186
1,187
1,188
1,189
1,190
1,191
1,192
1,193
1,194
1,195
1,196
1,197
1,198
1,199
1,200
1,201
1,202
1,203
1,204
1,205
1,206
1,207
1,208
1,209
1,210
1,211
1,212
1,213
1,214
1,215
1,216
1,217
1,218
1,219
1,220
1,221
1,222
1,223
1,224
1,225
1,226
1,227
1,228
1,229
1,230
1,231
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

Match case Limit results 1 per page

•

User actions, such as DHCP clear or disabling DHCP snooping

You can add a static DHCP snooping binding entry using the CLI. If you add a static entry for a client, any dynamic entry that is present for

the same client is overwritten. The switch does not remove static entries if it receives DHCP RELEASE or DHCP DECLINE packets.

By default, DHCP snooping is disabled globally and enabled on VLANs. For the DHCP snooping feature to work, enable it globally.

NOTE:

If you move a DHCP client from an untrusted interface to another untrusted interface within the VLAN, the

DHCP snooping binding database is not updated. The switch drops subsequent packets from the client. However, if you

move a DHCP client from an untrusted interface to a trusted interface, there is no impact to the traffic from the client.

Restrictions for DHCP snooping

•

The management VLAN does not support DHCP snooping.

•

VxLAN bridges do not support DHCP snooping.

•

The maximum number of supported DHCP snooping binding entries is 4000.

•

OS10 does not support multi-hop DHCP snooping.

•

For the DHCP snooping functionality to work correctly, ensure that the DHCP server supports option 82 (RFC 3046).

•

Enable option 82 (RFC 3046) on the DHCP server for the DHCP Snooping functionality to work correctly.

Rogue DHCP server detection

In the following topology, a trusted DHCP server, a DHCP client, and a rogue DHCP server are connected to the DHCP snooping switch.

The DHCP client and DHCP server are on the same VLAN. The physical interface eth 1/1/2 is a trusted interface. When the rogue DHCP

server sends a DHCP packet to the client, the switch analyzes the packet. As the rogue server is connected to the switch to an untrusted

eth 1/1/3 interface the switch deems the server as a rogue DHCP server and drops the packet.

DHCP snooping with DHCP relay

In the following topology, the DHCP snooping switch is the DHCP relay agent for DHCP clients on VLAN 100. The DHCP server is

reachable on VLAN 200 through eth 1/1/2. The switch forwards the client DHCP messages to the trusted DHCP server. The switch

processes DHCP packets from the DHCP server before forwarding them to DHCP clients. As the rogue server is connected to the switch

to the eth 1/1/3 interface which is untrusted, the switch drops DHCP packets from that interface.

206

System management