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Dell PowerEdge M420 Dell PowerConnect M8024-k User's Configuration Guide - Page 693

PFC Operation and Behavior, no-drop

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This feature is used in networks where the traffic has differing loss tolerances. For example, iSCSI and VoIP traffic are highly sensitive to traffic loss. If a link contains both loss-sensitive data and other less loss-sensitive data, the losssensitive data should use a no-drop priority that is enabled for flow control. Priorities are differentiated by the priority field of the IEEE 802.1Q VLAN header, which identifies an IEEE 802.1p priority value. These priority values must be mapped to internal class-of-service (CoS) values. The PFC feature allows you to specify the CoS values that should be paused (due to greater loss sensitivity) instead of dropped. when congestion occurs on a link. Unless configured as no-drop, all CoS priorities are considered nonpausable ("drop") when priority-based flow control is enabled. PFC Operation and Behavior PFC uses a new control packet defined in IEEE 802.1Qbb and therefore is not compatible with 802.3x flow control (FC). An interface that is configured for PFC will be automatically disabled for FC. When PFC is disabled on an interface, the FC configuration for the interface becomes active. Any FC frames received on a PFC configured interface are ignored. Each priority is configured as either drop or no-drop. If a priority that is designated as no-drop is congested, the priority is paused. Drop priorities do not participate in pause. When an interface is enabled for PFC, a manual configuration is applied. Even when interoperating with equipment that supports PFC negotiation, the connecting equipment should be configured in similar fashion. Interfaces that are not enabled for PFC do not act on PFC control frames. NOTE: This feature is configurable on physical full duplex interfaces only. If PFC is configured on a LAG interface, the member interfaces must have the same configuration. When PFC is disabled, the interface defaults to the IEEE 802.3x flow control setting for the interface. PFC is disabled by default. If you enable priority-based flow control for a particular priority value on an interface, ensure that Voice VLAN tagging is enabled on the interface so that the 802.1p priority values are carried through the network (see "Voice VLAN" on page 581). Additionally, make sure 802.1p priority values are mapped to CoS values (see "Configuring Class-of-Service" on page 1127). Configuring Port-Based Traffic Control 693

Section	Page
Introduction	49
About This Document	50
Audience	50
Document Conventions	50
Additional Documentation	51
Switch Features	53
System Management Features	54
Multiple Management Options	54
Simple Mode	54
Port Aggregator	55
System Time Management	55
Log Messages	55
Integrated DHCP Server	56
Management of Basic Network Information	56
IPv6 Management Features	56
Dual Software Images	56
File Management	57
Switch Database Management Templates	57
Automatic Installation of Firmware and Configuration	57
sFlow	58
SNMP Alarms and Trap Logs	58
CDP Interoperability through ISDP	58
Remote Monitoring (RMON)	58
Stacking Features (PCM6220 and PCM6348 Only)	59
High Port Count	59
Single IP Management	59
Automatic Firmware Upgrade for New Stack Members	59
Stacking Compatibility with the PowerConnect 7000 Series	59
Master Failover with Transparent Transition	60
Nonstop Forwarding on the Stack	60
Hot Add/Delete and Firmware Synchronization	60
Security Features	60
Configurable Access and Authentication Profiles	60
Password-Protected Management Access	61
Strong Password Enforcement	61
TACACS+ Client	61
RADIUS Support	61
SSH/SSL	62
Inbound Telnet Control	62
Denial of Service	62
Captive Portal	62
Dot1x Authentication (IEEE 802.1X)	63
MAC-Based 802.1X Authentication	63
Dot1x Monitor Mode	63
MAC-Based Port Security	63
Access Control Lists (ACL)	64
Time-Based ACLs	64
IP Source Guard (IPSG)	64
DHCP Snooping	65
Dynamic ARP Inspection	65
Protected Ports (Private VLAN Edge)	65
Switching Features	66
Flow Control Support (IEEE 802.3x)	66
Head of Line Blocking Prevention	66
Alternate Store and Forward (ASF)	66
Jumbo Frames Support	66
Auto-MDI/MDIX Support	66
VLAN-Aware MAC-based Switching	67
Back Pressure Support	67
Auto Negotiation	67
Broadcast Storm Control	67
Port Mirroring	68
Static and Dynamic MAC Address Tables	68
Link Layer Discovery Protocol (LLDP)	68
Link Layer Discovery Protocol (LLDP) for Media Endpoint Devices	68
Connectivity Fault Management (IEEE 802.1ag)	69
Cisco Protocol Filtering	69
DHCP Layer 2 Relay	69
Virtual Local Area Network Supported Features	70
VLAN Support	70
Port-Based VLANs	70
IP Subnet-based VLAN	70
MAC-based VLAN	70
IEEE 802.1v Protocol-Based VLANs	70
GARP and GVRP Support	71
Voice VLAN	71
Guest VLAN	71
Double VLANs	71
Spanning Tree Protocol Features	72
Spanning Tree Protocol (STP)	72
Spanning Tree Port Settings	72
Rapid Spanning Tree	72
Multiple Spanning Tree	72
Bridge Protocol Data Unit (BPDU) Guard	73
BPDU Filtering	73
Link Aggregation Features	73
Link Aggregation	73
Link Aggregate Control Protocol (LACP)	73
Routing Features	74
Address Resolution Protocol (ARP) Table Management	74
VLAN Routing	74
IP Configuration	74
Open Shortest Path First (OSPF)	74
BOOTP/DHCP Relay Agent	75
IP Helper and UDP Relay	75
Routing Information Protocol	75
Router Discovery	75
Routing Table	75
Virtual Router Redundancy Protocol (VRRP)	76
Tunnel and Loopback Interfaces	76
IPv6 Routing Features	76
IPv6 Configuration	76
IPv6 Routes	77
OSPFv3	77
DHCPv6	77
Quality of Service (QoS) Features	78
Differentiated Services (DiffServ)	78
Class Of Service (CoS)	78
Auto Voice over IP (VoIP)	78
Priority-based Flow Control (PFC)	79
Internet Small Computer System Interface (iSCSI) Optimization	79
Layer 2 Multicast Features	80
MAC Multicast Support	80
IGMP Snooping	80
IGMP Snooping Querier	80
MLD Snooping	80
Multicast VLAN Registration	81
Layer 3 Multicast Features	81
Distance Vector Multicast Routing Protocol	81
Internet Group Management Protocol	81
IGMP Proxy	81
Protocol Independent Multicast—Dense Mode	82
Protocol Independent Multicast—Sparse Mode	82
Protocol Independent Multicast—Source Specific Multicast	82
Protocol Independent Multicast IPv6 Support	82
MLD/MLDv2 (RFC2710/RFC3810)	82
Hardware Overview	83
PowerConnect M6220, M6348, M8024, and M8024-k Front Panel	83
PowerConnect M6220 Front Panel	83
PowerConnect M6348 Front Panel	85
PowerConnect M8024 Front Panel	86
PowerConnect M8024-k Front Panel	87
Console (RS-232) Port	87
Console Redirect	88
Out-of-Band Management Port	88
LED Definitions	89
Port LEDs	89
Module LEDs	91
System LEDs	93
Using Dell OpenManage Switch Administrator	95
About Dell OpenManage Switch Administrator	95
Starting the Application	96
Understanding the Interface	97
Defining Fields	99
Understanding the Device View	100
Using the Device View Port Features	100
Using the Command-Line Interface	101
Accessing the Switch Through the CLI	101
Console Connection	101
Telnet Connection	102
Understanding Command Modes	103
Entering CLI Commands	105
Using the Question Mark to Get Help	105
Using Command Completion	106
Entering Abbreviated Commands	106
Negating Commands	106
Understanding Error Messages	107
Recalling Commands from the History Buffer	107
Specifying Physical Ports	108
Default Settings	111
Setting the IP Address and Other Basic Network Information	115
IP Address and Network Information Overview	115
What Is the Basic Network Information?	115
Why Is Basic Network Information Needed?	116
How Is Basic Network Information Configured?	117
What Is Out-of-Band Management and In-Band Management?	117
Default Network Information	119
Configuring Basic Network Information (Web)	120
Out-of-Band Interface	120
IP Interface Configuration (Default VLAN IP Address)	121
Route Entry Configuration (Switch Default Gateway)	122
Domain Name Server	124
Default Domain Name	125
Host Name Mapping	126
Dynamic Host Name Mapping	127
Configuring Basic Network Information (CLI)	128
Enabling the DHCP Client on the OOB Port	128
Enabling the DHCP Client on the Default VLAN	128
Managing DHCP Leases	129
Configuring Static Network Information on the OOB Port	130
Configuring Static Network Information on the Default VLAN	130
Configuring and Viewing Additional Network Information	131
Basic Network Information Configuration Example	132
Managing a Switch Stack	135
Stacking Overview	135
Creating a PowerConnect M6220 Stack	136
Creating a PowerConnect M6348 Stack	137
PowerConnect 7000 Series and M6348 Stacking Compatibility	139
How is the Management Unit Selected?	139
Adding a Switch to the Stack	140
Removing a Switch from the Stack	141
How is the Firmware Updated on the Stack?	142
What is Stacking Standby?	142
What is Nonstop Forwarding?	142
Switch Stack MAC Addressing and Stack Design Considerations	145
NSF Network Design Considerations	146
Why is Stacking Needed?	146
Default Stacking Values	147
Managing and Monitoring the Stack (Web)	148
Unit Configuration	148
Stack Summary	150
Stack Firmware Synchronization	151
Supported Switches	152
Stack Port Summary	153
Stack Port Counters	154
Stack Port Diagnostics	154
NSF Summary	155
Checkpoint Statistics	156
Managing the Stack (CLI)	157
Configuring Stack Member and NSF Settings	157
Viewing and Clearing Stacking and NSF Information	158
Stacking and NSF Usage Scenarios	159
Basic Failover	160
Preconfiguring a Stack Member	162
NSF in the Data Center	164
NSF and VoIP	165
NSF and DHCP Snooping	166
NSF and the Storage Access Network	167
NSF and Routed Access	169
Controlling Management Access	171
Management Access Control Overview	171
What Are the Recommendations for Management Security?	173
What Is an Authentication Profile?	173
How Does TACACS+ Control Management Access?	174
How Does RADIUS Control Management Access?	176
What are RADIUS Server Groups?	178
How Does the Switch Determine Which RADIUS Server to Contact?	178
What Other Features Use Authentication?	180
Default Management Security Values	180
Controlling Management Access (Web)	182
Access Profile	182
Authentication Profiles	186
Select Authentication	190
Password Management	191
Last Password Set Result	193
User Login Configuration	194
Local User Database	195
Line Password	197
Enable Password	197
TACACS+ Settings	198
RADIUS Global Configuration	200
RADIUS Server Configuration	201
RADIUS Accounting Server Configuration	203
RADIUS Accounting Server Statistics	205
RADIUS Server Statistics	206
Authorization Network RADIUS	207
Telnet Server	208
Denial of Service	209
Secure HTTP Configuration	210
Secure Shell Configuration	213
Secure Public Key Configuration	214
Controlling Management Access (CLI)	216
Configuring a Management Access List	216
Adding Users to the Local Database	218
Configuring and Applying Authentication Profiles	219
Managing Passwords	220
Configuring RADIUS Server Information	222
Configuring TACACS+ Server Information	224
Configuring Telnet and SSH Access	225
Configuring HTTP and HTTPS Access	226
Configuring DoS Information	228
Management Access Configuration Examples	230
Configuring a Management Access List	230
Configuring the Primary and Secondary RADIUS Servers	231
Configuring an Authentication Profile	233
Configuring Password Lockout	234
Monitoring and Logging System Information	239
System Monitoring Overview	239
What System Information Is Monitored?	239
Why Is System Information Needed?	240
Where Are Log Messages Sent?	240
What Are the Severity Levels?	241
What Are the System Startup and Operation Logs?	241
What Is the Log Message Format?	242
What Factors Should Be Considered When Configuring Logging?	243
Default Log Settings	243
Monitoring System Information and Configuring Logging (Web)	244
Device Information	244
System Health	246
System Resources	247
Integrated Cable Test for Copper Cables	248
Optical Transceiver Diagnostics	249
Log Global Settings	251
RAM Log	252
Log File	253
Remote Log Server	253
Email Alert Global Configuration	256
Email Alert Mail Server Configuration	257
Email Alert Subject Configuration	259
Email Alert To Address Configuration	260
Email Alert Statistics	261
Monitoring System Information and Configuring Logging (CLI)	262
Viewing System Information	262
Running Cable Diagnostics	262
Configuring Local Logging	263
Configuring Remote Logging	265
Configuring Mail Server Settings	266
Configuring Email Alerts for Log Messages	267
Logging Configuration Examples	269
Configuring Local and Remote Logging	269
Configuring Email Alerting	271
Managing General System Settings	275
System Settings Overview	275
Why Does System Information Need to Be Configured?	276
What is Simple Mode?	277
What is the Port Aggregator Feature?	279
What Is the LAG Dependency Feature in Port Aggregator Mode?	280
What Are SDM Templates?	280
Why is the System Time Needed?	281
How Does SNTP Work?	281
What Configuration Is Required for Plug-In Modules?	282
Default General System Information	283
Default Port Aggregator Configurations	283
Configuring General System Settings (Web)	286
System Information	286
CLI Banner	289
SDM Template Preference	290
Operational Mode Configuration	291
Port Aggregator Global Configuration	293
Port Aggregator Port Configuration	294
Port Aggregator Group Configuration	296
Port Aggregator Internal Port VLAN Configuration	298
Port Aggregator Port Channel Summary	300
Group VLAN MAC Summary	301
Clock	302
SNTP Global Settings	303
SNTP Authentication	304
SNTP Server	306
Summer Time Configuration	310
Time Zone Configuration	311
Slot Summary	312
Supported Cards	313
Configuring System Settings (CLI)	314
Configuring System Information	314
Configuring the Banner	315
Managing the SDM Template	316
Configuring the Operational Mode and Port Aggregator Features	316
Configuring SNTP Authentication and an SNTP Server	318
Setting the System Time and Date Manually	320
Viewing Slot Information	321
General System Settings Configuration Examples	322
Configuring System and Banner Information	322
Configuring SNTP	324
Configuring the Time Manually	326
Configuring SNMP	327
SNMP Overview	327
What Is SNMP?	327
What Are SNMP Traps?	328
Why Is SNMP Needed?	329
Default SNMP Values	329
Configuring SNMP (Web)	331
SNMP Global Parameters	331
SNMP View Settings	332
Access Control Group	334
SNMPv3 User Security Model (USM)	335
Communities	338
Notification Filter	341
Notification Recipients	342
Trap Flags	345
OSPFv2 Trap Flags	346
OSPFv3 Trap Flags	347
Trap Log	348
Configuring SNMP (CLI)	349
Configuring the SNMPv3 Engine ID	349
Configuring SNMP Views, Groups, and Users	350
Configuring Communities	353
Configuring SNMP Notifications (Traps and Informs)	355
SNMP Configuration Examples	358
Configuring SNMPv1 and SNMPv2	358
Configuring SNMPv3	359
Managing Images and Files	363
Image and File Management Overview	363
What Files Can Be Managed?	363
Why Is File Management Needed?	365
What Methods Are Supported for File Management?	367
What Factors Should Be Considered When Managing Files?	367
How Is the Running Configuration Saved?	369
Managing Images and Files (Web)	370
File System	370
Active Images	371
File Download	372
File Upload	374
Copy Files	376
Managing Images and Files (CLI)	377
Downloading and Activating a New Image (TFTP)	377
Managing Files in Internal Flash	378
Uploading a Configuration File (SCP)	378
Managing Configuration Scripts (SFTP)	379
File and Image Management Configuration Examples	381
Upgrading the Firmware	381
Managing Configuration Scripts	384
Automatically Updating the Image and Configuration	387
Auto Configuration Overview	387
What Is the DHCP Auto Configuration Process?	387
Monitoring and Completing the DHCP Auto Configuration Process	392
What Are the Dependencies for DHCP Auto Configuration?	393
Default Auto Configuration Values	394
Managing Auto Configuration (Web)	395
Auto-Install Configuration	395
Managing Auto Configuration (CLI)	396
Managing Auto Configuration	396
Auto Configuration Example	397
Enabling DHCP Auto Configuration and Auto Image Download	397
Monitoring Switch Traffic	399
Traffic Monitoring Overview	399
What is sFlow Technology?	399
What is RMON?	402
What is Port Mirroring?	403
Why is Traffic Monitoring Needed?	404
Default Traffic Monitoring Values	404
Monitoring Switch Traffic (Web)	405
sFlow Agent Summary	405
sFlow Receiver Configuration	406
sFlow Sampler Configuration	407
sFlow Poll Configuration	408
Interface Statistics	409
Etherlike Statistics	410
GVRP Statistics	411
EAP Statistics	412
Utilization Summary	413
Counter Summary	414
Switchport Statistics	415
RMON Statistics	416
RMON History Control Statistics	417
RMON History Table	419
RMON Event Control	420
RMON Event Log	422
RMON Alarms	423
Port Statistics	425
LAG Statistics	426
Port Mirroring	427
Monitoring Switch Traffic (CLI)	429
Configuring sFlow	429
Configuring RMON	431
Viewing Statistics	433
Configuring Port Mirroring	434
Traffic Monitoring Configuration Examples	435
Configuring sFlow	435
Configuring RMON	437
Configuring iSCSI Optimization	439
iSCSI Optimization Overview	439
When Should iSCSI Optimization Be Enabled?	440
How Does the Switch Detect iSCSI Traffic Flows?	440
How Is Quality of Service Applied to iSCSI Traffic Flows?	440
What Information Does the Switch Track in iSCSI Traffic Flows?	441
How Does iSCSI Optimization Interact With Dell EqualLogic Arrays?	441
What Occurs When iSCSI is Enabled or Disabled?	442
Default iSCSI Optimization Values	443
Configuring iSCSI Optimization (Web)	444
iSCSI Global Configuration	444
iSCSI Targets Table	445
iSCSI Sessions Table	446
iSCSI Sessions Detailed	447
Configuring iSCSI Optimization (CLI)	448
iSCSI Optimization Configuration Examples	450
Configuring iSCSI Optimization Between Servers and a Disk Array	450
Configuring a Captive Portal	453
Captive Portal Overview	453
What Does a Captive Portal Do?	453
Is the Captive Portal Feature Dependent on Any Other Feature?	454
What Factors Should Be Considered When Designing and Configuring a Captive Portal?	455
How Does Captive Portal Work?	456
What Captive Portal Pages Can Be Customized?	457
Default Captive Portal Behavior and Settings	458
Configuring the Captive Portal (Web)	460
Captive Portal Global Configuration	460
Captive Portal Configuration	461
Local User	466
User Group	470
Interface Association	472
Captive Portal Global Status	473
Captive Portal Activation and Activity Status	474
Interface Activation Status	475
Interface Capability Status	476
Client Summary	477
Client Detail	478
Captive Portal Interface Client Status	479
Captive Portal Client Status	480
Configuring a Captive Portal (CLI)	481
Configuring Global Captive Portal Settings	481
Creating and Configuring a Captive Portal	482
Configuring Captive Portal Groups and Users	485
Managing Captive Portal Clients	486
Captive Portal Configuration Example	487
Configuration Overview	488
Detailed Configuration Procedures	489
Configuring Port Characteristics	491
Port Overview	491
What Physical Port Characteristics Can Be Configured?	491
What is Link Dependency?	493
What Interface Types are Supported?	494
What is Interface Configuration Mode?	495
Default Port Values	497
Configuring Port Characteristics (Web)	498
Port Configuration	498
Link Dependency Configuration	501
Link Dependency Summary	503
Configuring Port Characteristics (CLI)	504
Configuring Port Settings	504
Configuring Link Dependencies	505

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Match case Limit results 1 per page

Configuring Port-Based Traffic Control

693

This feature is used in networks where the traffic has differing loss tolerances.

For example, iSCSI and VoIP traffic are highly sensitive to traffic loss. If a link

contains both loss-sensitive data and other less loss-sensitive data, the loss-

sensitive data should use a no-drop priority that is enabled for flow control.

Priorities are differentiated by the priority field of the IEEE 802.1Q VLAN

header, which identifies an IEEE 802.1p priority value. These priority values

must be mapped to internal class-of-service (CoS) values.

The PFC feature allows you to specify the CoS values that should be paused

(due to greater loss sensitivity) instead of dropped. when congestion occurs

on a link. Unless configured as no-drop, all CoS priorities are considered non-

pausable (“drop”) when priority-based flow control is enabled.

PFC Operation and Behavior

PFC uses a new control packet defined in IEEE 802.1Qbb and therefore is

not compatible with 802.3x flow control (FC). An interface that is configured

for PFC will be automatically disabled for FC.

When PFC is disabled on an

interface, the FC configuration for the interface becomes active.

Any FC

frames received on a PFC configured interface are ignored.

Each priority is configured as either

drop

no-drop

If a priority that is

designated as no-drop is congested, the priority is paused. Drop priorities do

not participate in pause.

When an interface is enabled for PFC, a manual configuration is applied.

Even when interoperating with equipment that supports PFC negotiation,

the connecting equipment should be configured in similar fashion.

Interfaces

that are not enabled for PFC do not act on PFC control frames.

When PFC is disabled, the interface defaults to the IEEE 802.3x flow control

setting for the interface. PFC is disabled by default.

If you enable priority-based flow control for a particular priority value on an

interface, ensure that Voice VLAN tagging is enabled on the interface so that

the 802.1p priority values are carried through the network (see "Voice VLAN"

on page 581). Additionally, make sure 802.1p priority values are mapped to

CoS values (see "Configuring Class-of-Service" on page 1127).

NOTE:

This feature is configurable on physical full duplex interfaces only. If PFC

is configured on a LAG interface, the member interfaces must have the same

configuration.