Dell S4048T - Configure the Network Time Protocol; Enabling NTP

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Figure 133. NTP Fields

Implementation Information

Dell Networking systems can only be an NTP client.

Configure the Network Time Protocol

Configuring NTP is a one-step process.

• Enabling NTP

Related Configuration Tasks

• Configuring NTP Broadcasts

• Disabling NTP on an Interface

• Configuring a Source IP Address for NTP Packets (optional)

Enabling NTP

NTP is disabled by default.

To enable NTP, specify an NTP server to which the Dell Networking system synchronizes. To specify multiple

servers, enter the command multiple times. You may specify an unlimited number of servers at the expense

of CPU resources.

System Time and Date 1074

Main Page

Default Chapter3
- Table of Contents3
1 About this Guide37
- Audience37
- Conventions37
- Related Documents38
2 Configuration Fundamentals39
- Accessing the Command Line39
- CLI Modes40
  - Navigating CLI Modes41
- The Do Command45
- Undoing Commands45
- Obtaining Help46
- Entering and Editing Commands46
- Command History47
- Filtering Show Command Outputs48
  - Example of the Grep Keyword48
- Multiple Users in Configuration Mode49
3 Getting Started50
- Console Access51
  - Serial Console51
- Accessing the CLI Interface and Running Scripts Using SSH52
  - Entering CLI Commands Using an SSH Connection52
  - Executing Local CLI Scripts Using an SSH Connection53
- Default Configuration53
- Configuring a Host Name53
- Accessing the System Remotely54
- Configuring the Enable Password55
- Configuration File Management56
- Managing the File System64
- Enabling Software Features on Devices Using a Command Option64
- View Command History65
- Upgrading Dell Networking os65
- Verify Software Images before Installation66
- Using HTTP for File Transfers67
4 Management69
- Configuring Privilege Levels69
- Configuring Logging73
- Track Login Activity78
- Limit Concurrent Login Sessions81
- Log Messages in the Internal Buffer83
  - Configuration Task List for System Log Management83
- Disabling System Logging83
- Sending System Messages to a Syslog Server84
  - Configuring a UNIX System as a Syslog Server84
- Changing System Logging Settings84
- Display the Logging Buffer and the Logging Configuration85
- Configuring a UNIX Logging Facility Level86
- Synchronizing Log Messages87
- Enabling Timestamp on Syslog Messages88
- File Transfer Services88
- Terminal Lines90
  - Denying and Permitting Access to a Terminal Line91
  - Configuring Login Authentication for Terminal Lines92
- Setting Timeout for EXEC Privilege Mode93
- Using Telnet to Get to Another Network Device94
- Lock CONFIGURATION Mode94
  - Viewing the Configuration Lock Status95
- Restoring the Factory Default Settings95
  - Important Points to Remember96
  - Restoring Factory Default Environment Variables96
802.1Ag99
- Ethernet CFM99
- Maintenance Domains100
- Maintenance Points101
- Maintenance End Points101
- Implementation Information102
- Configuring the CFM102
  - Related Configuration Tasks103
- Enable Ethernet CFM103
- Creating a Maintenance Domain103
- Creating a Maintenance Association104
- Create Maintenance Points104
- Continuity Check Messages106
  - Enabling CCM107
  - Enabling Cross-Checking108
- Sending Loopback Messages and Responses108
- Sending Linktrace Messages and Responses109
  - Caching Link Trace110
- Enabling CFM SNMP Traps111
- Displaying Ethernet CFM Statistics112
802.1X116
- Port-Authentication Process116
  - EAP over RADIUS118
- Configuring 802.1X118
  - Related Configuration Tasks118
- Important Points to Remember119
- Enabling 802.1X120
- Configuring Request Identity Re-Transmissions122
  - Configuring a Quiet Period after a Failed Authentication122
- Forcibly Authorizing or Unauthorizing a Port123
- Re-Authenticating a Port124
- Configuring Timeouts125
- Configuring Dynamic VLAN Assignment with Port Authentication126
- Guest and Authentication-Fail Vlans127
  - Configuring a Guest VLAN128
  - Configuring an Authentication-Fail VLAN128
7 Access Control List (ACL) VLAN Groups and Content Addressable Memory (CAM)130
- Optimizing CAM Utilization During the Attachment of Acls to Vlans130
- Guidelines for Configuring ACL VLAN Groups131
- Configuring ACL VLAN Groups and Configuring FP Blocks for VLAN Parameters132
  - Configuring ACL VLAN Groups132
  - Configuring FP Blocks for VLAN Parameters133
- Viewing CAM Usage134
- Allocating FP Blocks for VLAN Processes135
8 Access Control Lists (Acls)137
- IP Access Control Lists (Acls)138
  - CAM Usage139
  - Implementing Acls on Dell Networking os140
- Important Points to Remember141
- IP Fragment Handling148
  - IP Fragments ACL Examples149
  - Layer 4 ACL Rules Examples149
- Configure a Standard IP ACL150
  - Configuring a Standard IP ACL Filter151
- Configure an Extended IP ACL152
  - Configuring Filters with a Sequence Number152
  - Configuring Filters Without a Sequence Number154
- Configure Layer 2 and Layer 3 Acls155
- Assign an IP ACL to an Interface155
- Applying an IP ACL156
  - Counting ACL Hits157
- Configure Ingress Acls157
- Configure Egress Acls158
  - Applying Egress Layer 3 Acls (Control-Plane)159
- IP Prefix Lists159
  - Implementation Information160
  - Configuration Task List for Prefix Lists160
- ACL Resequencing164
  - Resequencing an ACL or Prefix List165
- Route Maps166
  - Implementation Information166
- Logging of ACL Processes166
  - Guidelines for Configuring ACL Logging168
  - Configuring ACL Logging168
- Flow-Based Monitoring Support for Acls169
  - Behavior of Flow-Based Monitoring169
  - Enabling Flow-Based Monitoring171
- Configuring UDF ACL172
9 Bidirectional Forwarding Detection (BFD)176
- How BFD Works176
- Important Points to Remember182
- Configure BFD183
10 Border Gateway Protocol Ipv4 (Bgpv4)207
- Autonomous Systems (AS)207
- Sessions and Peers210
  - Establish a Session210
- Route Reflectors211
- BGP Attributes212
- Multiprotocol BGP218
- Implement BGP with Dell Networking os219
- Configuration Information225
- BGP Configuration226
- Enabling MBGP Configurations263
- BGP Regular Expression Optimization263
- Debugging BGP264
- Sample Configurations267
11 Content Addressable Memory (CAM)274
- CAM Allocation274
- Test CAM Usage276
- View CAM-ACL Settings277
- View CAM Usage279
- CAM Optimization279
- Troubleshoot CAM Profiling279
  - Qos CAM Region Limitation279
12 Control Plane Policing (Copp)281
- Configure Control Plane Policing283
13 Data Center Bridging (DCB)293
- Ethernet Enhancements in Data Center Bridging293
  - Priority-Based Flow Control295
  - Enhanced Transmission Selection296
  - Data Center Bridging Exchange Protocol (Dcbx)297
  - Data Center Bridging in a Traffic Flow298
- Enabling Data Center Bridging298
  - DCB Maps and Its Attributes299
- Data Center Bridging: Default Configuration300
- Configuring Priority-Based Flow Control301
  - Configuring Lossless Queues302
- Configuring PFC in a DCB Map303
  - PFC Configuration Notes303
  - PFC Prerequisites and Restrictions304
- Applying a DCB Map on a Port305
- Configuring PFC Without a DCB Map305
  - Configuring Lossless Queuesexample306
- Priority-Based Flow Control Using Dynamic Buffer Method308
  - Pause and Resume of Traffic308
  - Buffer Sizes for Lossless or PFC Packets309
- Behavior of Tagged Packets309
- Configuration Example for DSCP and PFC Priorities310
- Using PFC to Manage Converged Ethernet Traffic311
- Configure Enhanced Transmission Selection311
  - ETS Prerequisites and Restrictions311
  - Creating an ETS Priority Group312
  - ETS Operation with Dcbx313
  - Configuring Bandwidth Allocation for Dcbx CIN314
  - Configuring ETS in a DCB Map315
- Hierarchical Scheduling in ETS Output Policies316
- Using ETS to Manage Converged Ethernet Traffic317
- Applying DCB Policies in a Switch Stack317
- Configure a Dcbx Operation318
  - Dcbx Operation318
  - Dcbx Port Roles318
  - DCB Configuration Exchange320
  - Configuration Source Election321
  - Propagation of DCB Information321
  - Auto-Detection and Manual Configuration of the Dcbx Version322
  - Dcbx Example322
  - Dcbx Prerequisites and Restrictions323
  - Configuring Dcbx323
- Verifying the DCB Configuration327
- Qos Dot1P Traffic Classification and Queue Assignment338
- Configuring the Dynamic Buffer Method339
- Sample DCB Configuration340
  - PFC and ETS Configuration Command Examples342
14 Dynamic Host Configuration Protocol (DHCP)343
- DHCP Packet Format and Options343
- Assign an IP Address Using DHCP345
- Implementation Information346
- Configure the System to be a DHCP Server347
- Configure the System to be a Relay Agent351
- Configure the System to be a DHCP Client353
- Configure the System for User Port Stacking (Option 230)357
- Configure Secure DHCP357
- Source Address Validation365
15 Equal Cost Multi-Path (ECMP)368
- ECMP for Flow-Based Affinity368
- Link Bundle Monitoring369
- Rtag7372
- Flow-Based Hashing for ECMP373
16 FIP Snooping377
- Fibre Channel over Ethernet377
- Ensure Robustness in a Converged Ethernet Network377
- FIP Snooping on Ethernet Bridges379
- FIP Snooping in a Switch Stack382
- Using FIP Snooping382
- Displaying FIP Snooping Information387
- Fcoe Transit Configuration Example393
17 FIPS Cryptography395
- Configuration Tasks395
- Preparing the System396
- Enabling FIPS Mode396
- Generating Host-Keys397
- Monitoring FIPS Mode Status397
- Disabling FIPS Mode397
18 Force10 Resilient Ring Protocol (FRRP)399
- Protocol Overview399
- Implementing FRRP404
- FRRP Configuration405
- Troubleshooting FRRP409
  - Configuration Checks409
- Sample Configuration and Topology409
19 GARP VLAN Registration Protocol (GVRP)412
- Important Points to Remember412
- Configure GVRP414
  - Related Configuration Tasks415
- Enabling GVRP Globally415
- Enabling GVRP on a Layer 2 Interface415
- Configure GVRP Registration416
- Configure a GARP Timer416
- RPM Redundancy417
20 High Availability (HA)418
- Component Redundancy418
- Pre-Configuring a Stack Unit Slot421
- Removing a Provisioned Logical Stack Unit421
- Hitless Behavior422
- Graceful Restart422
- Software Resiliency423
- Hot-Lock Behavior424
21 Internet Group Management Protocol (IGMP)425
- IGMP Implementation Information425
- IGMP Protocol Overview426
  - IGMP Version 2426
  - IGMP Version 3427
- Configure IGMP431
  - Related Configuration Tasks431
- Viewing IGMP Enabled Interfaces431
- Selecting an IGMP Version432
- Viewing IGMP Groups432
- Adjusting Timers433
  - Adjusting Query and Response Timers433
- Preventing a Host from Joining a Group434
- Enabling IGMP Immediate-Leave437
- IGMP Snooping437
- Fast Convergence after MSTP Topology Changes440
- Egress Interface Selection (EIS) for HTTP and IGMP Applications440
- Designating a Multicast Router Interface450
22 Interfaces451
- Basic Interface Configuration451
- Advanced Interface Configuration451
- Interface Types452
- View Basic Interface Information453
- Resetting an Interface to Its Factory Default State455
- Enabling a Physical Interface455
- Physical Interfaces456
  - Configuration Task List for Physical Interfaces456
  - Overview of Layer Modes456
  - Configuring Layer 2 (Data Link) Mode457
  - Configuring Layer 2 (Interface) Mode457
  - Configuring Layer 3 (Network) Mode458
  - Configuring Layer 3 (Interface) Mode458
- Egress Interface Selection (EIS)459
  - Important Points to Remember459
  - Configuring EIS460
- Management Interfaces460
  - Configuring Management Interfaces460
  - Configuring a Management Interface on an Ethernet Port462
- VLAN Interfaces463
- Loopback Interfaces464
- Null Interfaces464
- Port Channel Interfaces465
  - Port Channel Definition and Standards465
  - Port Channel Benefits465
  - Port Channel Implementation465
  - Interfaces in Port Channels466
  - Configuration Tasks for Port Channel Interfaces466
  - Creating a Port Channel467
  - Adding a Physical Interface to a Port Channel467
  - Reassigning an Interface to a New Port Channel469
  - Configuring the Minimum Oper up Links in a Port Channel470
  - Adding or Removing a Port Channel from a VLAN470
  - Assigning an IP Address to a Port Channel472
  - Deleting or Disabling a Port Channel472
  - Load Balancing through Port Channels472
  - Changing the Hash Algorithm473
- Bulk Configuration473
  - Interface Range473
  - Bulk Configuration Examples474
- Defining Interface Range Macros476
  - Define the Interface Range476
  - Choosing an Interface-Range Macro476
- Monitoring and Maintaining Interfaces476
  - Maintenance Using TDR478
- Non Dell-Qualified Transceivers478
- Splitting QSFP Ports to SFP+ Ports479
- Converting a QSFP or QSFP+ Port to an SFP or SFP+ Port480
  - Important Points to Remember480
  - Example Scenarios481
- Link Dampening482
  - Important Points to Remember482
  - Enabling Link Dampening482
- Link Bundle Monitoring484
- Using Ethernet Pause Frames for Flow Control485
  - Enabling Pause Frames486
- Configure the MTU Size on an Interface486
- Port-Pipes487
- Auto-Negotiation on Ethernet Interfaces488
  - Setting the Speed and Duplex Mode of Ethernet Interfaces488
  - Set Auto-Negotiation Options490
- View Advanced Interface Information490
  - Configuring the Interface Sampling Size491
- Dynamic Counters493
  - Clearing Interface Counters493
23 Internet Protocol Security (Ipsec)495
- Configuring Ipsec496
24 Ipv4 Routing497
- IP Addresses498
  - Implementation Information498
- Configuration Tasks for IP Addresses498
- Assigning IP Addresses to an Interface499
- Configuring Static Routes500
- Configure Static Routes for the Management Interface501
- Ipv4 Path MTU Discovery Overview501
- Using the Configured Source IP Address in ICMP Messages502
  - Configuring the ICMP Source Interface502
- Configuring the Duration to Establish a TCP Connection503
- Enabling Directed Broadcast503
- Resolution of Host Names504
- Enabling Dynamic Resolution of Host Names504
- Specifying the Local System Domain and a List of Domains505
- Configuring DNS with Traceroute505
- Arp506
- Configuration Tasks for ARP506
- Configuring Static ARP Entries507
- Enabling Proxy ARP507
- Clearing ARP Cache508
- ARP Learning Via Gratuitous ARP508
- Enabling ARP Learning Via Gratuitous ARP509
- ARP Learning Via ARP Request509
- Configuring ARP Retries510
- Icmp511
- Configuration Tasks for ICMP511
- Enabling ICMP Unreachable Messages511
- UDP Helper512
  - Configure UDP Helper512
  - Important Points to Remember512
- Enabling UDP Helper512
- Configuring a Broadcast Address513
- Configurations Using UDP Helper513
- UDP Helper with Broadcast-All Addresses514
- UDP Helper with Subnet Broadcast Addresses515
- UDP Helper with Configured Broadcast Addresses515
- UDP Helper with no Configured Broadcast Addresses516
- Troubleshooting UDP Helper516
25 Ipv6 Routing518
- Protocol Overview518
- Implementing Ipv6 with Dell Networking os524
- Icmpv6527
- Path MTU Discovery527
- Ipv6 Neighbor Discovery528
  - Ipv6 Neighbor Discovery of MTU Packets529
- Configuration Task List for Ipv6 RDNSS529
- Secure Shell (SSH) over an Ipv6 Transport532
- Configuration Tasks for Ipv6532
- Configuring Ipv6 RA Guard539
  - Configuring Ipv6 RA Guard on an Interface541
  - Monitoring Ipv6 RA Guard541
26 Iscsi Optimization542
- Iscsi Optimization Overview542
- Default Iscsi Optimization Values549
- Iscsi Optimization Prerequisites549
- Configuring Iscsi Optimization549
- Displaying Iscsi Optimization Information552
27 Intermediate System to Intermediate System554
- IS-IS Protocol Overview554
- IS-IS Addressing555
- Multi-Topology IS-IS555
- Graceful Restart556
  - Timers557
- Implementation Information557
- Configuration Information558
- IS-IS Metric Styles575
- Configure Metric Values575
- Sample Configurations578
28 Link Aggregation Control Protocol (LACP)581
- Introduction to Dynamic Lags and LACP581
- LACP Configuration Tasks583
- Shared LAG State Tracking585
  - Configuring Shared LAG State Tracking586
  - Important Points about Shared LAG State Tracking588
- LACP Basic Configuration Example588
  - Configure a LAG on ALPHA588
29 Layer 2597
- Manage the MAC Address Table597
- MAC Learning Limit598
- NIC Teaming602
- Configure Redundant Pairs604
  - Important Points about Configuring Redundant Pairs606
- Far-End Failure Detection607
30 Link Layer Discovery Protocol (LLDP)613
- 802.1AB (LLDP) Overview613
  - Protocol Data Units613
- Optional Tlvs614
  - Management Tlvs615
- TIA-1057 (LLDP-MED) Overview617
  - TIA Organizationally Specific Tlvs617
- Configure LLDP622
- CONFIGURATION Versus INTERFACE Configurations622
- Enabling LLDP623
  - Disabling and Undoing LLDP623
- Enabling LLDP on Management Ports624
  - Disabling and Undoing LLDP on Management Ports624
- Advertising Tlvs624
- Viewing the LLDP Configuration626
- Viewing Information Advertised by Adjacent LLDP Agents626
- Configuring LLDPDU Intervals627
- Configuring Transmit and Receive Mode628
- Configuring the Time to Live Value629
- Debugging LLDP630
- Relevant Management Objects631
31 Microsoft Network Load Balancing637
- NLB Unicast Mode Scenario637
- NLB Multicast Mode Scenario638
- Limitations of the NLB Feature638
- Microsoft Clustering638
- Enable and Disable VLAN Flooding639
- Configuring a Switch for NLB639
  - Enabling a Switch for Multicast NLB639
32 Multicast Source Discovery Protocol (MSDP)641
- Protocol Overview641
- Anycast RP644
- Implementation Information644
- Configure Multicast Source Discovery Protocol644
  - Related Configuration Tasks645
- Enable MSDP649
- Manage the Source-Active Cache650
- Accept Source-Active Messages that Fail the RFP Check652
- Specifying Source-Active Messages655
- Limiting the Source-Active Messages from a Peer656
- Preventing MSDP from Caching a Local Source656
- Preventing MSDP from Caching a Remote Source657
- Preventing MSDP from Advertising a Local Source658
- Logging Changes in Peership States659
- Terminating a Peership659
- Clearing Peer Statistics660
- Debugging MSDP660
- MSDP with Anycast RP661
- Configuring Anycast RP662
  - Reducing Source-Active Message Flooding663
  - Specifying the RP Address Used in SA Messages663
- MSDP Sample Configurations666
33 Multiple Spanning Tree Protocol (MSTP)669
- Protocol Overview669
- Spanning Tree Variations671
  - Implementation Information671
- Configure Multiple Spanning Tree Protocol671
  - Related Configuration Tasks671
- Enable Multiple Spanning Tree Globally672
- Adding and Removing Interfaces672
- Creating Multiple Spanning Tree Instances673
- Influencing MSTP Root Selection674
- Interoperate with Non-Dell Bridges675
- Changing the Region Name or Revision675
- Modifying Global Parameters676
- Modifying the Interface Parameters677
- Configuring an Edgeport678
- Flush MAC Addresses after a Topology Change679
- MSTP Sample Configurations680
  - Router 1 Running-Configurationrouter 2 Running-Configurationrouter 3 Running-Configurationsftos Example Running-Configuration680
- Debugging and Verifying MSTP Configurations683
34 Multicast Features686
- Enabling IP Multicast686
- Implementation Information686
- Multicast Policies687
  - Ipv4 Multicast Policies687
35 Object Tracking695
- Object Tracking Overview695
- Object Tracking Configuration699
- Displaying Tracked Objects706
36 Open Shortest Path First (Ospfv2 and Ospfv3)708
- Protocol Overview708
- OSPF with Dell Networking os715
- Configuration Information719
- Configuration Task List for Ospfv3 (OSPF for Ipv6)750
37 Policy-Based Routing (PBR)767
- Overview767
- Implementing PBR768
- Configuration Task List for Policy-Based Routing769
- Sample Configuration774
  - 2/11View Redirect-List GOLD776
38 PIM Sparse-Mode (PIM-SM)779
- Implementation Information779
- Protocol Overview779
- Configuring PIM-SM781
  - Related Configuration Tasks781
- Enable PIM-SM781
- Configuring S,G Expiry Timers782
- Configuring a Static Rendezvous Point783
  - Overriding Bootstrap Router Updates784
- Configuring a Designated Router784
- Creating Multicast Boundaries and Domains785
39 PIM Source-Specific Mode (PIM-SSM)786
- Implementation Information786
  - Important Points to Remember787
- Configure PIM-SSM787
  - Related Configuration Tasks787
- Enabling PIM-SSM787
- Use PIM-SSM with IGMP Version 2 Hosts788
  - Configuring PIM-SSM with Igmpv2788
40 Port Monitoring791
- Important Points to Remember791
- Port Monitoring792
- Configuring Port Monitoring794
- Configuring Monitor Multicast Queue795
- Enabling Flow-Based Monitoring796
- Remote Port Mirroring797
- Encapsulated Remote Port Monitoring804
- ERPM Behavior on a Typical Dell Networking os806
  - Decapsulation of ERPM Packets at the Destination IP/ Analyzer807
41 Private Vlans (PVLAN)809
- Private VLAN Concepts809
- Using the Private VLAN Commands810
- Configuration Task List811
- Private VLAN Configuration Example816
- Inspecting the Private VLAN Configuration817
42 Per-VLAN Spanning Tree Plus (PVST+)820
- Protocol Overview820
- Implementation Information821
- Configure Per-VLAN Spanning Tree Plus822
  - Related Configuration Tasks822
- Enabling PVST822
- Disabling PVST823
- Influencing PVST+ Root Selection824
- Modifying Global PVST+ Parameters825
- Modifying Interface PVST+ Parameters826
- Configuring an Edgeport827
- PVST+ in Multi-Vendor Networks828
- Enabling PVST+ Extend System ID828
- PVST+ Sample Configurations829
43 Quality of Service (Qos)832
- Implementation Information835
- Port-Based Qos Configurations835
- Policy-Based Qos Configurations838
- DSCP Color Maps849
- Enabling Qos Rate Adjustment851
- Enabling Strict-Priority Queueing852
- Weighted Random Early Detection852
- Pre-Calculating Available Qos CAM Space855
- Configuring Weights and ECN for WRED856
  - Global Service Pools with WRED and ECN Settings857
- Configuring WRED and ECN Attributes858
- Guidelines for Configuring ECN for Classifying and Color-Marking Packets859
- Applying Layer 2 Match Criteria on a Layer 3 Interface864
- Applying DSCP and VLAN Match Criteria on a Service Queue864
- Classifying Incoming Packets Using ECN and Color-Marking865
- Guidelines for Configuring ECN for Classifying and Color-Marking Packets868
- Sample Configuration to Mark Non-Ecn Packets as "Yellow" with Multiple Traffic Class868
- Sample Configuration to Mark Non-Ecn Packets as "Yellow" with Single Traffic Class869
- Enabling Buffer Statistics Tracking870
44 Routing Information Protocol (RIP)873
- Protocol Overview873
  - Ripv1873
  - Ripv2874
- Implementation Information874
- Configuration Information874
  - Configuration Task List875
  - RIP Configuration Example881
45 Remote Monitoring (RMON)887
- Implementation Information887
- Fault Recovery888
46 Rapid Spanning Tree Protocol (RSTP)892
- Protocol Overview892
- Configuring Rapid Spanning Tree892
  - Related Configuration Tasks892
- Important Points to Remember893
  - RSTP and VLT893
- Configuring Interfaces for Layer 2 Mode893
- Enabling Rapid Spanning Tree Protocol Globally894
- Adding and Removing Interfaces896
- Modifying Global Parameters897
  - Enabling SNMP Traps for Root Elections and Topology Changes898
- Modifying Interface Parameters898
- Enabling SNMP Traps for Root Elections and Topology Changes899
- Influencing RSTP Root Selection899
- Configuring an Edgeport900
- Configuring Fast Hellos for Link State Detection901
47 Software-Defined Networking (SDN)902
48 Security903
- AAA Accounting903
  - Configuration Task List for AAA Accounting903
- AAA Authentication906
  - Configuration Task List for AAA Authentication906
- Obscuring Passwords and Keys909
- AAA Authorization910
  - Privilege Levels Overview910
  - Configuration Task List for Privilege Levels910
- Radius915
- Tacacs920
- Protection from TCP Tiny and Overlapping Fragment Attacks923
- Enabling SCP and SSH923
- Telnet931
- VTY Line and Access-Class Configuration932
- Role-Based Access Control934
49 Service Provider Bridging947
- VLAN Stacking947
- VLAN Stacking Packet Drop Precedence957
- Dynamic Mode Cos for VLAN Stacking960
  - Mapping C-Tag to S-Tag Dot1P Values961
- Layer 2 Protocol Tunneling962
- Provider Backbone Bridging967
50 Sflow969
- Overview969
- Implementation Information970
  - Important Points to Remember970
- Enabling Extended Sflow971
- Enabling and Disabling Sflow on an Interface972
- Enabling Sflow Max-Header Size Extended972
- Sflow Show Commands973
- Configuring Specify Collectors975
- Changing the Polling Intervals975
- Back-Off Mechanism976
- Sflow on LAG Ports976
- Enabling Extended Sflow976
  - Important Points to Remember977
51 Simple Network Management Protocol (SNMP)979
- Protocol Overview980
- Implementation Information980
- Snmpv3 Compliance with FIPS980
- Configuration Task List for SNMP981
  - Related Configuration Tasks982
- Important Points to Remember982
- Set up SNMP982
  - Creating a Community982
  - Setting up User-Based Security (Snmpv3)983
- Reading Managed Object Values984
- Writing Managed Object Values985
- Configuring Contact and Location Information Using SNMP986
- Subscribing to Managed Object Value Updates Using SNMP987
- Enabling a Subset of SNMP Traps988
- Enabling an SNMP Agent to Notify Syslog Server Failure990
- Copy Configuration Files Using SNMP991
  - Copying a Configuration File993
  - Copying Configuration Files Via SNMP994
  - Copying the Startup-Config Files to the Running-Config994
  - Copying the Startup-Config Files to the Server Via FTP995
  - Copying the Startup-Config Files to the Server Via TFTP995
  - Copy a Binary File to the Startup-Configuration996
  - Additional MIB Objects to View Copy Statistics996
  - Obtaining a Value for MIB Objects997
- MIB Support to Display the Available Memory Size on Flash998
  - Viewing the Available Flash Memory Size998
- MIB Support to Display the Software Core Files Generated by the System999
  - Viewing the Software Core Files Generated by the System999
- Manage Vlans Using SNMP1000
  - Creating a VLAN1000
  - Assigning a VLAN Alias1000
  - Displaying the Ports in a VLAN1001
  - Add Tagged and Untagged Ports to a VLAN1002
- Managing Overload on Startup1003
- Enabling and Disabling a Port Using SNMP1004
- Fetch Dynamic MAC Entries Using SNMP1004
- Deriving Interface Indices1006
- Monitor Port-Channels1007
- Enabling an SNMP Agent to Notify Syslog Server Failure1008
- Troubleshooting SNMP Operation1009
52 Stacking1011
- Stacking Overview1011
- Important Points to Remember1021
- Stacking Installation Tasks1021
- Stacking Configuration Tasks1029
- Verify a Stack Configuration1035
  - Displaying the Status of Stacking Ports1035
- Remove Units or Front End Ports from a Stack1037
  - Removing a Unit from a Stack1037
  - Removing Front End Port Stacking1038
- Troubleshoot a Stack1039
  - Recover from Stack Link Flaps1039
  - Recover from a Card Problem State on a Stack1039
53 Storm Control1041
- Configure Storm Control1041
  - Configuring Storm Control from INTERFACE Mode1042
  - Configuring Storm Control from CONFIGURATION Mode1042
54 Spanning Tree Protocol (STP)1044
- Protocol Overview1044
- Configure Spanning Tree1045
  - Related Configuration Tasks1045
- Important Points to Remember1045
- Configuring Interfaces for Layer 2 Mode1046
- Enabling Spanning Tree Protocol Globally1047
- Adding an Interface to the Spanning Tree Group1050
- Modifying Global Parameters1050
- Modifying Interface STP Parameters1051
- Enabling Portfast1052
  - Prevent Network Disruptions with BPDU Guard1053
- Selecting STP Root1055
- STP Root Guard1055
  - Root Guard Scenario1056
  - Configuring Root Guard1057
- Enabling SNMP Traps for Root Elections and Topology Changes1057
- Configuring Spanning Trees as Hitless1058
- STP Loop Guard1058
  - Configuring Loop Guard1059
- Displaying STP Guard Configuration1060
55 Supportassist1062
- Configuring Supportassist Using a Configuration Wizard1063
- Configuring Supportassist Manually1063
- Configuring Supportassist Activity1065
- Configuring Supportassist Company1067
- Configuring Supportassist Person1068
- Configuring Supportassist Server1069
- Viewing Supportassist Configuration1069
56 System Time and Date1072
- Network Time Protocol1072
- Dell Networking os Time and Date1080
57 Tunneling1084
- Configuring a Tunnel1084
- Configuring Tunnel Keepalive Settings1085
- Configuring a Tunnel Interface1086
- Configuring Tunnel Allow-Remote Decapsulation1086
- Configuring the Tunnel Source Anylocal1087
58 Uplink Failure Detection (UFD)1088
- Feature Description1088
- How Uplink Failure Detection Works1089
- UFD and NIC Teaming1090
- Important Points to Remember1091
- Configuring Uplink Failure Detection1091
- Clearing a UFD-Disabled Interface1093
- Displaying Uplink Failure Detection1094
- Sample Configuration: Uplink Failure Detection1096
59 Upgrade Procedures1098
- Get Help with Upgrades1098
60 Virtual Lans (Vlans)1099
- Default VLAN1100
- Port-Based Vlans1100
- Vlans and Port Tagging1101
- Configuration Task List1101
- Configuring Native Vlans1105
- Enabling Null VLAN as the Default VLAN1106
61 VLT Proxy Gateway1107
- Proxy Gateway in VLT Domains1107
- Configuring an LLDP VLT Proxy Gateway1112
- Configuring a Static VLT Proxy Gateway1113
62 Virtual Link Trunking (VLT)1114
- Overview1114
  - VLT on Core Switches1115
  - Enhanced VLT1116
- VLT Terminology1116
- Configure Virtual Link Trunking1117
- RSTP Configuration1129
- PVST+ Configuration1142
  - Sample PVST+ Configuration1142
- Evlt Configuration Example1143
  - Evlt Configuration Step Examples1144
- PIM-Sparse Mode Configuration Example1146
- Verifying a VLT Configuration1147
- Additional VLT Sample Configurations1150
- Troubleshooting VLT1152
- Reconfiguring Stacked Switches as VLT1154
- Specifying VLT Nodes in a PVLAN1154
- Configuring a VLT VLAN or LAG in a PVLAN1159
  - Creating a VLT LAG or a VLT VLAN1159
  - Associating the VLT LAG or VLT VLAN in a PVLAN1160
- Proxy ARP Capability on VLT Peer Nodes1161
  - Working of Proxy ARP for VLT Peer Nodes1162
- VLT Nodes as Rendezvous Points for Multicast Resiliency1163
- Configuring VLAN-Stack over VLT1164
- Ipv6 Peer Routing in VLT Domains Overview1167
63 Virtual Extensible LAN (VXLAN)1174
- Overview1174
- Components of VXLAN Network1175
- Functional Overview of VXLAN Gateway1176
- VXLAN Frame Format1176
  - Components of VXLAN Frame Format1177
- Configuring and Controlling VXLAN from the NVP Controller GUI1178
- Configuring Vxlan Gateway1181
  - Connecting to an NVP Controller1181
  - Advertising VXLAN Access Ports to Controller1182
- Displaying VXLAN Configurations1184
- VXLAN Service Nodes for BFD1185
  - Examples of the Show Bfd Neighbors Command1185
64 Virtual Routing and Forwarding (VRF)1186
- VRF Overview1186
- VRF Configuration Notes1187
  - Dhcp1190
- VRF Configuration1190
- Sample VRF Configuration1195
- Route Leaking Vrfs1201
- Dynamic Route Leaking1202
  - Configuring Route Leaking Without Filtering Criteria1202
  - Configuring Route Leaking with Filtering1205
65 Virtual Router Redundancy Protocol (VRRP)1209
- VRRP Overview1209
- VRRP Benefits1210
- VRRP Implementation1210
- VRRP Configuration1211
  - Configuration Task List1211
    - Creating a Virtual Router1212
    - Configuring Vrrp Authentication1216
  - Setting VRRP Initialization Delay1221
- Sample Configurations1222
66 Debugging and Diagnostics1237
- Offline Diagnostics1237
  - Important Points to Remember1237
  - Running Offline Diagnostics1237
- Trace Logs1241
- Auto Save on Crash or Rollover1241
- Last Restart Reason1241
- Hardware Watchdog Timer1241
- Using the Show Hardware Commands1242
- Enabling Environmental Monitoring1243
- Buffer Tuning1247
- Troubleshooting Packet Loss1252
- Enabling Application Core Dumps1260
- Mini Core Dumps1261
- Enabling TCP Dumps1262
67 Standards Compliance1263
- IEEE Compliance1263
- RFC and I-D Compliance1264
- MIB Location1277

Dell S4048T - Configure the Network Time Protocol; Enabling NTP

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