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Dell PowerConnect 8100 Series User's Configuration Guide - Page 147

How is the Firmware Updated on the Stack?, What is Stacking Standby?, What is Nonstop Forwarding?

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How is the Firmware Updated on the Stack? When you add a new switch to a stack, the Stack Firmware Synchronization feature automatically synchronizes the firmware version with the version running on the stack master per the configuration on the master switch. The synchronization operation may result in either upgrade or downgrade of firmware on the mismatched stack member. Upgrading the firmware on a stack of switches is the same as upgrading the firmware on a single switch. After you download a new image by using the File Download page or copy command, the downloaded image is distributed to all the connected units of the stack. For more information about downloading and installing images, see "Managing Images and Files" on page 307. What is Stacking Standby? A standby unit is preconfigured in the stack. If the current stack master fails, the standby unit becomes the stack master. If no switch is pre-configured as the standby unit, the software automatically selects a standby unit from the existing stack units. When the failed master resumes normal operation, it joins the stack as a member (not a master) if the new stack master has already been elected. The stack master copies its running configuration to the standby unit whenever it changes (subject to some restrictions to reduce overhead). This enables the standby unit to take over the stack operation with minimal interruption if the stack master becomes unavailable. Operational state synchronization also occurs: • when you save the running configuration to the startup configuration on the stack master. • when the backup unit changes. What is Nonstop Forwarding? Networking devices are often described in terms of three semi-independent functions called the forwarding plane, the control plane, and the management plane. The forwarding plane forwards data packets and is implemented in hardware. The control plane is the set of protocols that determine how the forwarding plane should forward packets, deciding which data packets are allowed to be forwarded and where they should go. Managing a Switch Stack 147

Section	Page
Introduction	49
About This Document	49
Audience	50
Document Conventions	50
Additional Documentation	51
Switch Features	53
System Management Features	54
Multiple Management Options	54
System Time Management	54
Log Messages	54
Integrated DHCP Server	55
Management of Basic Network Information	55
IPv6 Management Features	55
Dual Software Images	55
File Management	56
Switch Database Management Templates	56
Automatic Installation of Firmware and Configuration	56
sFlow	57
SNMP Alarms and Trap Logs	57
CDP Interoperability through ISDP	57
Remote Monitoring (RMON)	57
Stacking Features	58
High Port Count	58
Single IP Management	58
Automatic Firmware Update for New Stack Members	58
Master Failover with Transparent Transition	59
Nonstop Forwarding on the Stack	59
Hot Add/Delete and Firmware Synchronization	59
Security Features	59
Configurable Access and Authentication Profiles	59
Password-Protected Management Access	60
Strong Password Enforcement	60
TACACS+ Client	60
RADIUS Support	60
SSH/SSL	61
Inbound Telnet Control	61
Denial of Service	61
Port Protection	61
Captive Portal	62
Dot1x Authentication (IEEE 802.1X)	62
MAC-Based 802.1X Authentication	62
Dot1x Monitor Mode	63
MAC-Based Port Security	63
Access Control Lists (ACL)	63
Time-Based ACLs	64
IP Source Guard (IPSG)	64
DHCP Snooping	64
Dynamic ARP Inspection	64
Protected Ports (Private VLAN Edge)	65
Switching Features	65
Flow Control Support (IEEE 802.3x)	65
Head of Line Blocking Prevention	65
Alternate Store and Forward (ASF)	65
Jumbo Frames Support	66
Auto-MDI/MDIX Support	66
VLAN-Aware MAC-based Switching	66
Back Pressure Support	66
Auto Negotiation	67
Broadcast Storm Control	67
Port Mirroring	67
Static and Dynamic MAC Address Tables	68
Link Layer Discovery Protocol (LLDP)	68
Link Layer Discovery Protocol (LLDP) for Media Endpoint Devices	68
Priority-based Flow Control (PFC)	68
Data Center Bridging Exchange (DBCx) Protocol	69
Enhanced Transmission Selection	69
Fibre Channel over Ethernet (FCoE) Initialization Protocol Snooping	69
Cisco Protocol Filtering	70
DHCP Layer 2 Relay	70
Virtual Local Area Network Supported Features	70
VLAN Support	70
Port-Based VLANs	70
IP Subnet-based VLAN	71
MAC-based VLAN	71
IEEE 802.1v Protocol-Based VLANs	71
GARP and GVRP Support	71
Voice VLAN	71
Guest VLAN	72
Double VLANs	72
Spanning Tree Protocol Features	73
Spanning Tree Protocol (STP)	73
Spanning Tree Port Settings	73
Rapid Spanning Tree	73
Multiple Spanning Tree	73
Bridge Protocol Data Unit (BPDU) Guard	74
BPDU Filtering	74
Link Aggregation Features	74
Link Aggregation	74
Link Aggregate Control Protocol (LACP)	74
Routing Features	76
Address Resolution Protocol (ARP) Table Management	76
VLAN Routing	76
IP Configuration	76
Open Shortest Path First (OSPF)	76
BOOTP/DHCP Relay Agent	77
IP Helper and UDP Relay	77
Routing Information Protocol	77
Router Discovery	77
Routing Table	77
Virtual Router Redundancy Protocol (VRRP)	78
Tunnel and Loopback Interfaces	78
IPv6 Routing Features	78
IPv6 Configuration	78
IPv6 Routes	79
OSPFv3	79
DHCPv6	79
Quality of Service (QoS) Features	80
Differentiated Services (DiffServ)	80
Class Of Service (CoS)	80
Auto Voice over IP (VoIP)	80
Internet Small Computer System Interface (iSCSI) Optimization	81
Layer 2 Multicast Features	81
MAC Multicast Support	81
IGMP Snooping	81
IGMP Snooping Querier	82
MLD Snooping	82
Multicast VLAN Registration	82
Layer 3 Multicast Features	83
Distance Vector Multicast Routing Protocol	83
Internet Group Management Protocol	83
IGMP Proxy	83
Protocol Independent Multicast—Dense Mode	83
Protocol Independent Multicast—Sparse Mode	84
Protocol Independent Multicast—Source Specific Multicast	84
Protocol Independent Multicast IPv6 Support	84
MLD/MLDv2 (RFC2710/RFC3810)	84
Hardware Overview	85
PowerConnect 8000-series and 8100-series Front Panel	85
PowerConnect 8024 Front Panel	85
PowerConnect 8024F Front Panel	86
PowerConnect 8132 Front Panel	87
PowerConnect 8132F Front Panel	87
PowerConnect 8164 Front Panel	88
PowerConnect 8164F Front Panel	89
Hot-Pluggable Interface Modules	90
USB Port (Power Connect 8100-series switches only)	92
Port and System LEDs	92
PowerConnect 8000-series and 8100-series Back Panel	92
Console Port	93
Out-of-Band Management Port	93
Power Supplies	93
Ventilation System	94
LED Definitions	95
Port LEDs	95
System LEDs	96
Switch Addresses	97
Using Dell OpenManage Switch Administrator	101
About Dell OpenManage Switch Administrator	101
Starting the Application	102
Understanding the Interface	103
Defining Fields	105
Understanding the Device View	106
Using the Device View Port Features	106
Using the Command-Line Interface	107
Accessing the Switch Through the CLI	107
Console Connection	107
Telnet Connection	108
Understanding Command Modes	109
Entering CLI Commands	111
Using the Question Mark to Get Help	111
Using Command Completion	112
Entering Abbreviated Commands	112
Negating Commands	112
Understanding Error Messages	113
Recalling Commands from the History Buffer	113
Default Settings	115
Setting the IP Address and Other Basic Network Information	119
IP Address and Network Information Overview	119
What Is the Basic Network Information?	119
Why Is Basic Network Information Needed?	120
How Is Basic Network Information Configured?	121
What Is Out-of-Band Management and In-Band Management?	121
Default Network Information	123
Configuring Basic Network Information (Web)	124
Out-of-Band Interface	124
IP Interface Configuration (Default VLAN IP Address)	125
Route Entry Configuration (Switch Default Gateway)	126
Domain Name Server	128
Default Domain Name	129
Host Name Mapping	130
Dynamic Host Name Mapping	131
Configuring Basic Network Information (CLI)	132
Enabling the DHCP Client on the OOB Port	132
Enabling the DHCP Client on the Default VLAN	132
Managing DHCP Leases	133
Configuring Static Network Information on the OOB Port	134
Configuring Static Network Information on the Default VLAN	134
Configuring and Viewing Additional Network Information	135
Basic Network Information Configuration Example	136
Managing QSFP Ports	139
Managing a Switch Stack	141
Stacking Overview	141
Creating a PowerConnect 8000/8100 Series Stack	142
How is the Stack Master Selected?	144
Adding a Switch to the Stack	145
Removing a Switch from the Stack	146
How is the Firmware Updated on the Stack?	147
What is Stacking Standby?	147
What is Nonstop Forwarding?	147
Switch Stack MAC Addressing and Stack Design Considerations	150
NSF Network Design Considerations	151
Why is Stacking Needed?	151
Default Stacking Values	152
Managing and Monitoring the Stack (Web)	153
Unit Configuration	153
Stack Summary	155
Stack Firmware Synchronization	156
Supported Switches	157
Stack Port Summary	158
Stack Port Counters	159
Stack Port Diagnostics	159
NSF Summary	160
Checkpoint Statistics	161
Managing the Stack (CLI)	162
Configuring Stack Member, Stack Port, and NSF Settings	162
Viewing and Clearing Stacking and NSF Information	164
Stacking and NSF Usage Scenarios	164
Basic Failover	166
Preconfiguring a Stack Member	168
NSF in the Data Center	170
NSF and VoIP	171
NSF and DHCP Snooping	172
NSF and the Storage Access Network	173
NSF and Routed Access	175
Configuring Authentication, Authorization, and Accounting	177
AAA Overview	177
Methods	178
Access Lines	179
Authentication	179
Authorization	180
Exec Authorization Capabilities	181
Accounting	182
Authentication Examples	183
Local Authentication Example	183
TACACS+ Authentication Example	184
RADIUS Authentication Example	186
Authorization Examples	187
Local Authorization Example—Direct Login to Privileged EXEC Mode	187
TACACS+ Authorization Example—Direct Login to Privileged EXEC Mode	187
TACACS+ Authorization Example—Administrative Profiles	188
TACACS+ Authorization Example—Custom Administrative Profile	189
TACACS+ Authorization Example—Per-command Authorization	190
RADIUS Authorization Example—Direct Login to Privileged EXEC Mode	191
RADIUS Authorization Example—Administrative Profiles	191
Using RADIUS Servers to Control Management Access	192
How Does RADIUS Control Management Access?	192
Which RADIUS Attributes Does the Switch Support?	194
How Are RADIUS Attributes Processed on the Switch?	196
Using TACACS+ Servers to Control Management Access	197
Which TACACS+ Attributes Does the Switch Support?	198
Default Configurations	199
Method Lists	199
Access Lines (AAA)	199
Access Lines (Non-AAA)	200
Administrative Profiles	200
Monitoring and Logging System Information	203
System Monitoring Overview	203
What System Information Is Monitored?	203
Why Is System Information Needed?	204
Where Are Log Messages Sent?	204
What Are the Severity Levels?	205
What Are the System Startup and Operation Logs?	205
What Is the Log Message Format?	206
What Factors Should Be Considered When Configuring Logging?	207
Default Log Settings	207
Monitoring System Information and Configuring Logging (Web)	208
Device Information	208
System Health	209
System Resources	210
Integrated Cable Test for Copper Cables	211
Optical Transceiver Diagnostics	212
Log Global Settings	214
RAM Log	215
Log File	216
Remote Log Server	216
Email Alert Global Configuration	219
Email Alert Mail Server Configuration	220
Email Alert Subject Configuration	222
Email Alert To Address Configuration	223
Email Alert Statistics	224
Monitoring System Information and Configuring Logging (CLI)	225
Viewing System Information	225
Running Cable Diagnostics	225
Configuring Local Logging	226
Configuring Remote Logging	228
Configuring Mail Server Settings	229
Configuring Email Alerts for Log Messages	230
Logging Configuration Examples	232
Configuring Local and Remote Logging	232
Configuring Email Alerting	233
Managing General System Settings	237
System Settings Overview	237
Why Does System Information Need to Be Configured?	238
What Are SDM Templates?	239
Why is the System Time Needed?	240
How Does SNTP Work?	240
Default General System Information	240
Configuring General System Settings (Web)	241
System Information	241
CLI Banner	244
SDM Template Preference	245
Clock	246
SNTP Global Settings	247
SNTP Authentication	248
SNTP Server	250
Summer Time Configuration	254
Time Zone Configuration	255
Slot Summary	256
Supported Cards	257
Configuring System Settings (CLI)	258
Configuring System Information	258
Configuring the Banner	259
Managing the SDM Template	260
Configuring SNTP Authentication and an SNTP Server	260
Setting the System Time and Date Manually	262
Viewing Slot Information	263
General System Settings Configuration Examples	264
Configuring System and Banner Information	264
Configuring SNTP	267
Configuring the Time Manually	269
Configuring SNMP	271
SNMP Overview	271
What Is SNMP?	271
What Are SNMP Traps?	272
Why Is SNMP Needed?	273
Default SNMP Values	273
Configuring SNMP (Web)	275
SNMP Global Parameters	275
SNMP View Settings	276
Access Control Group	278
SNMPv3 User Security Model (USM)	280
Communities	283
Notification Filter	285
Notification Recipients	286
Trap Flags	289
OSPFv2 Trap Flags	290
OSPFv3 Trap Flags	291
Trap Log	292
Configuring SNMP (CLI)	293
Configuring the SNMPv3 Engine ID	293
Configuring SNMP Views, Groups, and Users	294
Configuring Communities	297
Configuring SNMP Notifications (Traps and Informs)	299
SNMP Configuration Examples	302
Configuring SNMPv1 and SNMPv2	302
Configuring SNMPv3	303
Managing Images and Files	307
Image and File Management Overview	307
What Files Can Be Managed?	307
Why Is File Management Needed?	309
What Methods Are Supported for File Management?	311
What Factors Should Be Considered When Managing Files?	311
How Is the Running Configuration Saved?	313
Managing Images and Files (Web)	314
File System	314
Active Images	315
USB Flash Drive	316
File Download	317
File Upload	319
Copy Files	321
Managing Images and Files (CLI)	322
Downloading and Activating a New Image (TFTP)	322
Managing Files in Internal Flash	323
Managing Files on a USB Flash Device (PowerConnect 8100-series switches only)	324
Uploading a Configuration File (SCP)	324
Managing Configuration Scripts (SFTP)	325
File and Image Management Configuration Examples	326
Upgrading the Firmware	326
Managing Configuration Scripts	329
Managing Files by Using the USB Flash Drive (PowerConnect 8100- series switches only)	331
Automatically Updating the Image and Configuration	333
Auto Configuration Overview	333
What Is USB Auto Configuration?	334
What Files Does USB Auto Configuration Use?	334
What Is the DHCP Auto Configuration Process?	335
Monitoring and Completing the DHCP Auto Configuration Process	339
What Are the Dependencies for DHCP Auto Configuration?	340
Default Auto Configuration Values	341
Managing Auto Configuration (Web)	342
Auto-Install Configuration	342
Managing Auto Configuration (CLI)	343
Managing Auto Configuration	343
Auto Configuration Example	344
Enabling DHCP Auto Configuration and Auto Image Download	344
Monitoring Switch Traffic	347
Traffic Monitoring Overview	347
What is sFlow Technology?	347
What is RMON?	350
What is Port Mirroring?	351
Why is Traffic Monitoring Needed?	352
Default Traffic Monitoring Values	352
Monitoring Switch Traffic (Web)	353
sFlow Agent Summary	353
sFlow Receiver Configuration	354
sFlow Sampler Configuration	355
sFlow Poll Configuration	356
Interface Statistics	357
Etherlike Statistics	358
GVRP Statistics	359
EAP Statistics	360
Utilization Summary	361
Counter Summary	362
Switchport Statistics	363
RMON Statistics	364
RMON History Control Statistics	365
RMON History Table	367
RMON Event Control	368
RMON Event Log	370
RMON Alarms	371
Port Statistics	373
LAG Statistics	374
Port Mirroring	375
Monitoring Switch Traffic (CLI)	378
Configuring sFlow	378
Configuring RMON	380
Viewing Statistics	382
Configuring Port Mirroring	383
Traffic Monitoring Configuration Examples	384
Configuring sFlow	384
Configuring RMON	386
Configuring iSCSI Optimization	387
iSCSI Optimization Overview	387
What Does iSCSI Optimization Do?	388
How Does the Switch Detect iSCSI Traffic Flows?	388
How Is Quality of Service Applied to iSCSI Traffic Flows?	388
How Does iSCSI Optimization Use ACLs?	389
What Information Does the Switch Track in iSCSI Traffic Flows?	389
How Does iSCSI Optimization Interact With Dell EqualLogic Arrays?	390
What Occurs When iSCSI Optimization Is Enabled or Disabled?	390
How Does iSCSI Optimization Interact with DCBx?	391
How Does iSCSI Optimization Interact with Dell Compellent Arrays?	391
Default iSCSI Optimization Values	392
Configuring iSCSI Optimization (Web)	393
iSCSI Global Configuration	393
iSCSI Targets Table	394
iSCSI Sessions Table	395
iSCSI Sessions Detailed	396
Configuring iSCSI Optimization (CLI)	397
iSCSI Optimization Configuration Examples	399
Configuring iSCSI Optimization Between Servers and a Disk Array	399
Configuring a Captive Portal	401
Captive Portal Overview	401
What Does a Captive Portal Do?	401
Is the Captive Portal Feature Dependent on Any Other Feature?	402
What Factors Should Be Considered When Designing and Configuring a Captive Portal?	403
How Does Captive Portal Work?	404
What Captive Portal Pages Can Be Customized?	405
Default Captive Portal Behavior and Settings	406
Configuring the Captive Portal (Web)	408
Captive Portal Global Configuration	408
Captive Portal Configuration	409
Local User	414
User Group	418
Interface Association	420
Captive Portal Global Status	421
Captive Portal Activation and Activity Status	422
Interface Activation Status	423
Interface Capability Status	424
Client Summary	425
Client Detail	426
Captive Portal Interface Client Status	427
Captive Portal Client Status	428
Configuring a Captive Portal (CLI)	429
Configuring Global Captive Portal Settings	429
Creating and Configuring a Captive Portal	430
Configuring Captive Portal Groups and Users	433
Managing Captive Portal Clients	434
Captive Portal Configuration Example	435
Configuration Overview	436
Detailed Configuration Procedures	437
Configuring Port Characteristics	439
Port Overview	439
What Physical Port Characteristics Can Be Configured?	439
What is Link Dependency?	440
What Interface Types are Supported?	442
What is Interface Configuration Mode?	442
Default Port Values	444
Configuring Port Characteristics (Web)	445
Port Configuration	445
Link Dependency Configuration	448
Link Dependency Summary	450
Configuring Port Characteristics (CLI)	451
Configuring Port Settings	451
Configuring Link Dependencies	452
Port Configuration Examples	454
Configuring Port Settings	454
Configuring a Link Dependency Groups	455
Configuring Port and System Security	457
IEEE 802.1X	458
What is IEEE 802.1X?	458
What are the 802.1X Port States?	459
What is MAC-Based 802.1X Authentication?	460
What is the Role of 802.1X in VLAN Assignment?	461
What is Monitor Mode?	463
How Does the Authentication Server Assign DiffServ Filters?	465
What is the Internal Authentication Server?	465
Default 802.1X Values	466
Configuring IEEE 802.1X (Web)	467
Configuring IEEE 802.1X (CLI)	476
Configuring Internal Authentication Server Users	481

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Match case Limit results 1 per page

Managing a Switch Stack

147

How is the Firmware Updated on the Stack?

When you add a new switch to a stack, the Stack Firmware Synchronization

feature automatically synchronizes the firmware version with the version

running on the stack master per the configuration on the master switch. The

synchronization operation may result in either upgrade or downgrade of

firmware on the mismatched stack member.

Upgrading the firmware on a stack of switches is the same as upgrading the

firmware on a single switch. After you download a new image by using the File

Download page or

copy

command, the downloaded image is distributed to all

the connected units of the stack. For more information about downloading

and installing images, see "Managing Images and Files" on page 307.

What is Stacking Standby?

A standby unit is preconfigured in the stack. If the current stack master fails,

the standby unit becomes the stack master. If no switch is pre-configured as

the standby unit, the software automatically selects a standby unit from the

existing stack units.

When the failed master resumes normal operation, it joins the stack as a

member (not a master) if the new stack master has already been elected.

The stack master copies its running configuration to the standby unit

whenever it changes (subject to some restrictions to reduce overhead). This

enables the standby unit to take over the stack operation with minimal

interruption if the stack master becomes unavailable.

Operational state synchronization also occurs:

•

when you save the running configuration to the startup configuration on

the stack master.

•

when the backup unit changes.

What is Nonstop Forwarding?

Networking devices are often described in terms of three semi-independent

functions called the forwarding plane, the control plane, and the

management plane. The forwarding plane forwards data packets and is

implemented in hardware. The control plane is the set of protocols that

determine how the forwarding plane should forward packets, deciding which

data packets are allowed to be forwarded and where they should go.