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Dell S5000 FTOS 9.0(1.3) Configuration Guide for the Switch - Page 470

UDP Helper with Subnet Broadcast Addresses,

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www.dell.com | support.dell.com 3. Packet 2 is also forwarded to the ingress interface with an unchanged destination address because it does not have broadcast address configured. Figure 22-13. UDP helper with All Broadcast Addresses Packet 1 Destination Address: 255.255.255.255 VLAN 100 IP address: 1.1.0.1/24 Subnet broadcast address: 1.1.0.255 Configured broadcast address: 1.1.255.255 Hosts on VLAN 100: 1.1.0.2, 1.1.0.3, 1.1.0.4 1/1 1/2 Ingress interface IP Address: 2.1.1.1/24 UDP helper enabled Packet 2 Switched Packet 1/3 VLAN 101 IP address: 1.11.1/24 Subnet broadcast address: 1.1.1.255 Configured broadcast address: 1.1.255.255 Hosts on VLAN 100: 1.1.1.2, 1.1.1.3, 1.1.1.4 UDP Helper with Subnet Broadcast Addresses When the destination IP address of an incoming packet matches the subnet broadcast address of any interface, the system changes the address to the configured broadcast address and sends it to matching interfaces. In the following illustration, Packet 1 has the destination IP address 1.1.1.255, which matches the subnet broadcast address of VLAN 101. If UDP helper is configured and the packet matches the specified UDP port, then the system changes the address to the configured IP broadcast address and floods the packet on VLAN 101. Packet 2 is sent from host on VLAN 101. It has a broadcast MAC address and a destination IP address of 1.1.1.255. In this case, it is flooded on VLAN 101 in its original condition as the forwarding process is Layer 2. Figure 22-14. UDP helper with Subnet Broadcast Addresses Preamble Start Frame Destination MAC Source MAC Delimiter (01:80:C2:00:00:0E) Ethernet Type (0x88CC) LLDPDU Padding FCS TLV 1 Chassis ID TLV 2 Port ID TLV 3 Port Description TLV 4 TLV 5 TLV 6 TLV 7 TLV 127 TLV 0 System Name System Description System Capabilities Management Addr Organizationally Specific End of LLDPDU UDP Helper with Configured Broadcast Addresses Incoming packets with a destination IP address matching the configured broadcast address of any interface are forwarded to the matching . 470 | IPv4 Routing

Section	Page
About this Guide	29
Objectives	29
Audience	29
Conventions	29
Related Documents	30
Configuration Fundamentals	31
Accessing the Command Line	31
CLI Modes	32
Navigating CLI Modes	34
Port Numbering Convention	36
The do Command	37
The no Command	37
Obtaining Help	38
Entering and Editing Commands	39
Command History	40
Filtering show Command Outputs	40
Multiple Users in Configuration mode	42
Getting Started	43
Accessing Ports	44
Accessing the RJ-45/RS-232 Console Port	44
Accessing the RJ-45 console port with a DB-9 adapter	45
Accessing the USB-B Console Port	45
Booting Process	47
Entering the Initial Configuration Information	49
Configuring the Enable Password	50
Configuring a Host Name	51
Navigating CLI Modes	51
Default Configuration	51
Configuring Layer 2 (Data Link) Mode	51
Accessing the System Remotely	52
Configuring the Management Port IP Address	52
Configuring a Management Route	53
Configuring a Username and Password	53
Creating a Port-based VLAN	53
Assigning Interfaces to a VLAN	54
Assigning an IP Address to a VLAN	55
Connecting the S5000 to the Network	55
Configuring File Management	55
Copying Files to and from the System	56
Important Points to Remember	56
Saving the Running-configuration	57
Configuring the Overload bit for Startup Scenario	58
Viewing Files	58
Viewing Configuration Files	59
File System Management	60
Viewing command history	61
Upgrading and Downgrading FTOS	62
Switch Management	63
Configuring Privilege Levels	64
Creating a Custom Privilege Level	64
Removing a command from EXEC mode	64
Moving a command from EXEC privilege mode to EXEC mode	64
Allowing Access to CONFIGURATION mode commands	64
Allowing Access to INTERFACE, LINE, ROUTE-MAP, and ROUTER modes	65
Applying a Privilege Level to a Username	67
Applying a Privilege Level to a Terminal Line	67
Configuring Logging	67
Disabling Logging	67
Log Messages in the Internal Buffer	68
Configuring Task List for System Log Management	68
Disabling System Logging	68
Sending System Messages to a Syslog Server	68
Configuring a Unix System as a Syslog Server	68
Changing System Logging Settings	69
Displaying the Logging Buffer and the Logging Configuration	70
Configuring a UNIX logging facility level	71
Synchronizing log messages	72
Enabling timestamp on syslog messages	72
File Transfer Services	73
Configuring Task List for File Transfer Services	73
Enabling FTP server	73
Configuring FTP server parameters	74
Configuring FTP client parameters	74
Terminal Lines	75
Denying and Permitting Access to a Terminal Line	75
Configuring Login Authentication for Terminal Lines	76
Timing out of EXEC Privilege Mode	77
Telneting to Another Network Device	78
Locking CONFIGURATION mode	78
Viewing the Configuration Lock Status	79
Recovering from a Forgotten Password	80
Recovering from a Forgotten Enable Password	80
Recovering from a Failed Start	81
802.1ag	83
Ethernet CFM	84
Maintenance Domains	84
Maintenance Points	85
Maintenance End Points	86
Implementation Information	86
Configuring CFM	86
Related Configuration Tasks	87
Enabling Ethernet CFM	87
Creating a Maintenance Domain	87
Creating a Maintenance Association	88
Creating Maintenance Points	88
Creating a Maintenance End Point	88
Creating a Maintenance Intermediate Point	89
MP Databases	89
Continuity Check Messages	90
Enabling CCM	92
Enabling Cross-checking	92
Loopback Message and Response	92
Linktrace Message and Response	92
Enabling Link Trace Cache	93
Enabling CFM SNMP Traps	94
Displaying Ethernet CFM Statistics	95
802.1X	97
Protocol Overview	97
Port-authentication Process	99
EAP over RADIUS	100
RADIUS Attributes for 802.1 Support	100
Configuring 802.1X	101
Related Configuration Tasks	101
Important Points to Remember	101
Enabling 802.1X	101
Configuring Request Identity Re-transmissions	103
Configuring a Quiet Period after a Failed Authentication	104
Forcibly Authorizing or Unauthorizing a Port	105
Re-authenticating a Port	106
Periodic Re-authentication	106
Configuring Timeouts	107
Dynamic VLAN Assignment with Port Authentication	108
Guest and Authentication-fail VLANs	109
Configuring a Guest VLAN	110
Configuring an Authentication-fail VLAN	110
Access Control Lists (ACLs)	113
Overview	113
IP Access Control Lists (ACLs)	114
CAM Allocation and CAM Optimization	115
User-Configurable CAM Allocation	115
CAM optimization	115
Test CAM Usage	116
Implementing ACLs on FTOS	116
ACLs and VLANs	116
ACL Optimization	117
Determine the Order in Which ACLs are Used to Classify Traffic	117
IP Fragment Handling	118
IP Fragments ACL Examples	118
Layer 4 ACL Rules Examples	119
Configuring a Standard IP ACL	120
Configuring an Extended IP ACL	123
Configuring filters with a Sequence Number	123
Configuring Filters without a Sequence Number	124
Established Flag	125
To obtain the functionality of est, use the following ACLs:	125
Configuring Layer 2 and Layer 3 ACLs on an Interface	125
Assigning an IP ACL to an Interface	126
Counting ACL Hits	127
Configuring Ingress ACLs	127
Configuring Egress ACLs	128
Egress Layer 3 ACL Lookup for Control-plane IP Traffic	129
Configuring ACLs to Loopback	130
Applying an ACL on Loopback Interfaces	130
IP Prefix Lists	131
Implementation Information	132
Configuration Task List for Prefix Lists	132
Configuring a prefix list	132
Using a prefix list for route redistribution	135
ACL Resequencing	136
Resequencing an ACL or Prefix List	137
Route Maps	138
Implementation Information	138
Important Points to Remember	138
Configuration Task List for Route Maps	139
Creating a route map	139
Configuring Route Map Filters	141
Configuring a route map for route redistribution	143
Configuring a route map for route tagging	144
Continue clause	145
Bidirectional Forwarding Detection (BFD)	147
Protocol Overview	147
How BFD Works	148
Configuring Bidirectional Forwarding Detection	153
Configuring BFD for Physical Ports	154
Changing physical port session parameters	157
Configuring BFD for Static Routes	158
Configuring BFD for OSPF	160
Configuring BFD for IS-IS	163
Configuring BFD for BGP	165
Configuring BFD for VRRP	173
Configuring BFD for VLANs	176
Changing session parameters	177
Configuring BFD for Port-Channels	178
Changing port-channel session parameters	180
Configuring Protocol Liveness	180
Troubleshooting BFD	181
Border Gateway Protocol IPv4 (BGPv4)	183
Protocol Overview	184
Autonomous Systems (AS)	184
Sessions and Peers	186
Route Reflectors	187
Confederations	188
BGP Attributes	189
Best Path Selection Criteria	189
Weight	192
Local Preference	192
Origin	193
AS Path	194
Next Hop	195
Multiprotocol BGP	195
Implementing BGP with FTOS	195
Additional Path (Add-Path) support	195
Advertising IGP cost as MED for redistributed routes	195
Ignoring Router-ID for some best-path calculations	196
4-Byte AS Numbers	197
AS4 Number Representation	197
AS Number Migration	200
BGP4 Management Information Base (MIB)	202
Important Points to Remember	202
Configuration Information	203
BGP Configuration	204
Configuration Task List for BGP	204
MBGP Configuration	246
BGP Regular Expression Optimization	247
Debugging BGP	247
Storing Last and Bad PDUs	248
Capturing PDUs	250
PDU Counters	251
Sample Configurations	251
Bare Metal Provisioning 2.0	263
Prerequisites	264
Restrictions	264
Overview	264
Jumpstart mode	265
DHCP Server	265
File Server	268
Domain Name Server	269
Switch boot and set-up behavior in Jumpstart Mode	269
Content Addressable Memory (CAM)	273
Content Addressable Memory	273
CAM Allocation	273
Re-allocating CAM for Ingress ACLs and QoS	274
Re-allocating CAM for Egress ACLs	275
Testing CAM Usage for QoS Policies	275
Displaying CAM-ACL Settings	276
Displaying CAM-ACL-Egress Settings	277
CAM Optimization	277
Control Plane Policing (CoPP)	279
Overview	279
Configuring Control Plane Policing	280
Configuring CoPP for protocols	281
Sample Config for CoPP protocol configuration	282
Configuring CoPP for CPU queues	283
Sample Config for CoPP CPU queue configuration	283
Show commands	284
Data Center Bridging (DCB)	287
Ethernet Enhancements in Data Center Bridging	287
Priority-Based Flow Control	288
Enhanced Transmission Selection	289
Data Center Bridging Exchange Protocol	291
Data Center Bridging in a Traffic Flow	291
Data Center Bridging: Default Configuration	292
Enabling Data Center Bridging	292
QoS dot1p Traffic Classification and Queue Assignment	293
Configuring PFC and ETS in a DCB Map	294
PFC Configuration Notes	294
PFC Prerequisites and Restrictions	295
ETS Configuration Notes	296
ETS Prerequisites and Restrictions	297
Priority-Group Configuration Notes	297
DCB Map: Configuration Procedure	297
Applying a DCB Map on a Port	299
Configuring PFC without a DCB Map	299
Configuring Lossless Queues	300
ETS Operation with DCBx	301
Configuring Bandwidth Allocation for DCBx CIN	302
Applying a DCB Map in a Switch Stack	302
Configuring DCBx Operation	303
Supported DCBx Versions	303
DCBx Operation	303
DCBx Port Roles	304
DCB Configuration Exchange	305
Configuration Source Election	306
Propagation of DCB Information	306
Auto-Detection and Manual Configuration of the DCBx Version	307
DCBx Example	308
DCBx Prerequisites and Restrictions	309
DCBx Configuration Procedure	310
Verifying DCB Configuration	313
PFC and ETS Configuration Examples	325
Using PFC and ETS to Manage Data Center Traffic	325
Using PFC and ETS to Manage Converged Ethernet Traffic in a Switch Stack	329
Hierarchical Scheduling in ETS Configuration	329
Troubleshooting PFC, ETS, and DCBx Operation	330
DCBx Oper Status is Down	330
DCBx Error Messages	331
Debugging DCBx on an Interface	332
Dynamic Host Configuration Protocol (DHCP)	333
Protocol Overview	333
DHCP Packet Format and Options	334
Assigning an IP Address using DHCP	335
Implementation Information	336
Configuration Tasks	336
Configuring the System to be a DHCP Server	336
Configuration Tasks	337
Related Configuration Tasks	337
Configuring the Server for Automatic Address Allocation	337
Specifying a Default Gateway	338
Enabling DHCP Server	339
Configuring a Method of Hostname Resolution	339
Creating Manual Binding Entries	340
Debugging DHCP server	341
DHCP Clear Commands	341
Configuring the System to be a Relay Agent	341
Configuring the System for User Port Stacking	342
Configuring Secure DHCP	343
Option 82	343
DHCP Snooping	344
Dropping DHCP packets on snooped VLANs only	346
Dynamic ARP Inspection	347
Source Address Validation	349
Equal Cost Multi-Path (ECMP)	353
ECMP for Flow-based Affinity	353
Deterministic ECMP Next Hop	353
Configuring Hash Algorithm Seed	354
Link Bundle Monitoring	354
Managing ECMP Group Paths	355
FCoE Transit	357
Fibre Channel over Ethernet	357
Ensuring Robustness in a Converged Ethernet Network	357
FIP Snooping on Ethernet Bridges	359
Configuring FIP Snooping	361
Enabling the FCoE Transit Feature	361
Enabling FIP Snooping on VLANs	362
Configuring the FC-MAP Value	363
Configuring a Port for a Bridge-to-FCF Link	363
FIP Snooping on an NPIV Proxy Gateway	363
FIP Snooping in an S5000 Stack	363
Impact on Other Software Features	364
FIP Snooping Prerequisites	364
FIP Snooping Restrictions	365
FIP Snooping Configuration Procedure	366
Displaying FIP Snooping Information	367
FCoE Transit Configuration Example	372
Force10 Resilient Ring Protocol (FRRP)	375
Protocol Overview	375
Ring Status	376
Multiple FRRP Rings	377
Important FRRP Points	379
Important FRRP Concepts	379
Implementing FRRP	380
Configuring FRRP	381
Troubleshooting FRRP	385
Configuration Checks	385
Sample Configuration and Topology	385
GARP VLAN Registration Protocol (GVRP)	387
Protocol Overview	387
Important Points to Remember	387
Configuring GVRP	388
Related Configuration Tasks	389
Enabling GVRP Globally	389
Enabling GVRP on a Layer 2 Interface	390
Configuring GVRP Registration	390
Configuring a GARP Timer	391
High Availability	393
High Availability on S5000 Stacks	393
Hitless Behavior	393
Graceful Restart	394
Software Resiliency	394
System Health Monitoring	394
Failure and Event Logging	394
Hot-lock Behavior	395
Internet Group Management Protocol (IGMP)	397
IGMP Implementation Information	397
IGMP Protocol Overview	398
IGMP version 2	398
IGMP version 3	399
Configuring IGMP	402
Related Configuration Tasks	402
Viewing IGMP Enabled Interfaces	402
Selecting an IGMP Version	403
Viewing IGMP Groups	403
Adjusting Timers	404
Adjusting Query and Response Timers	404
Adjusting the IGMP Querier Timeout Value	404
Configuring a Static IGMP Group	405
Enabling IGMP Immediate-leave	405
IGMP Snooping	405
IGMP Snooping Implementation Information	406
Configuring IGMP Snooping	406
Enabling IGMP Immediate-leave	406
Disabling Multicast Flooding	407
Specifying a Port as Connected to a Multicast Router	407
Configuring the Switch as Querier	407
Fast Convergence after MSTP Topology Changes	408
Designating a Multicast Router Interface	408
Interfaces	409
Basic Interface Configuration:	409
Advanced Interface Configuration:	409
Interface Types	410
Viewing Basic Interface Information	410
Enabling a Physical Interface	413
Physical Interfaces	413
Configuration Task List for Physical Interfaces	414
Overview of Layer Modes	414
Configuring Layer 2 (Data Link) Mode	414
Configuring Layer 3 (Network) Mode	415
Management Interfaces	417
Configuring a Management Interface	417
Important Things to Remember — virtual-ip	418
Displaying a Management Interface Configuration	419
VLAN Interfaces	420
Loopback Interfaces	421
Port Channel Interfaces	421
Port channel definition and standards	421
Port channel benefits	422
Port channel implementation	422
1G/10G interfaces in port channels	422
Configuration task list for port channel interfaces	423
Creating a port channel	423
Adding a physical interface to a port channel	424
Reassigning an interface to a new port channel	426
Configuring the minimum oper up links in a port channel (LAG)	427
Adding or removing a port channel from a VLAN	428
Assigning an IP address to a port channel	428
Deleting or disabling a port channel	429
Load balancing through port channels	429
S5000 load-balancing	429
Hash algorithm	430
Bulk Configuration	431
Interface Range	431
Bulk Configuration Examples	431
Interface Range Macros	433
Defining the Interface Range	433
Choosing an Interface-range Macro	434
Monitoring and Maintaining Interfaces	434
Splitting QSFP ports to SFP+ ports	436
Important Points	436
Link Dampening	437
Important Points to Remember	437
Enabling Link Dampening	437
Link Bundle Monitoring	439
Using Ethernet Pause Frames for Flow Control	440
Configuring MTU Size on an Interface	441
Adjusting the keepalive timer	442
Viewing Advanced Interface Information	442
Displaying Only Configured Interfaces	442
Configuring Interface Sampling Size	443
Dynamic Counters	445
Clearing interface counters	446
Fibre Channel Interfaces	447
Configuring Fibre Channel Interfaces	447
Enabling Fibre Channel Capability	447
Configuring Fibre Channel Interfaces	447
Displaying Fibre Channel Information	448
Troubleshooting Fibre Channel Operation	452
IPv4 Routing	455
IP Addresses	456
Implementation Information	456
Configuration Task List for IP Addresses	456
Directed Broadcast	460
Resolution of Host Names	460
ARP	463
Configuration Task List for ARP	463
ARP Learning via Gratuitous ARP	465
ARP Learning via ARP Request	465
Configuring ARP Retries	466
ICMP	466
Configuration Task List for ICMP	466
UDP Helper	467
Configuring UDP Helper	467
Important Points to Remember about UDP Helper	467
Enabling UDP Helper	468
Configuring a Broadcast Address	468
Configurations Using UDP Helper	469
UDP Helper with Broadcast-all Addresses	469
UDP Helper with Subnet Broadcast Addresses	470
UDP Helper with Configured Broadcast Addresses	470
UDP Helper with No Configured Broadcast Addresses	471
Troubleshooting UDP Helper	471
iSCSI Optimization	473
iSCSI Optimization Overview	473
Monitoring iSCSI Traffic Flows	475
Application of Quality of Service to iSCSI Traffic Flows	475
Information Monitored in iSCSI Traffic Flows	475
Detection and Auto-configuration for Dell EqualLogic Arrays	476
Detection and Port Configuration for Dell Compellent Arrays	476
Enabling and Disabling iSCSI Optimization	477
Default iSCSI Optimization Values	478
iSCSI Optimization Prerequisites	478
Configuring iSCSI Optimization	479
Displaying iSCSI Optimization Information	480
Intermediate System to Intermediate System	483
Protocol Overview	483
IS-IS Addressing	484
Multi-Topology IS-IS	484
Transition Mode	485
Interface support	485
Adjacencies	485
Graceful Restart	486
Timers	486
Implementation Information	487
Configuration Information	488
Configuration Task List for IS-IS	488
Configuring the distance of a route	498
Changing the IS-type	498
IS-IS Metric Styles	505
Configuring Metric Values	506
Maximum Values in the Routing Table	506
Changing the IS-IS Metric Style in One Level Only	506

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470

IPv4 Routing

www.dell.com

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Packet 2 is also forwarded to the ingress interface with an unchanged destination address because it

does not have broadcast address configured.

Figure 22-13.

UDP helper with All Broadcast Addresses

UDP Helper with Subnet Broadcast Addresses

When the destination IP address of an incoming packet matches the subnet broadcast address of any

interface, the system changes the address to the configured broadcast address and sends it to matching

interfaces.

In the following illustration, Packet 1 has the destination IP address 1.1.1.255, which matches the subnet

broadcast address of VLAN 101. If UDP helper is configured and the packet matches the specified UDP

port, then the system changes the address to the configured IP broadcast address and floods the packet on

VLAN 101.

Packet 2 is sent from host on VLAN 101. It has a broadcast MAC address and a destination IP address of

1.1.1.255. In this case, it is flooded on VLAN 101 in its original condition as the forwarding process is

Layer 2.

Figure 22-14.

UDP helper with Subnet Broadcast Addresses

UDP Helper with Configured Broadcast Addresses

Incoming packets with a destination IP address matching the configured broadcast address of any interface

are forwarded to the matching .

Packet 1

Destination Address:

255.255.255.255

1/1

Ingress interface

IP Address: 2.1.1.1/24

UDP helper enabled

1/2

1/3

VLAN 100

IP address: 1.1.0.1/24

Subnet broadcast address: 1.1.0.255

Configured broadcast address: 1.1.255.255

Hosts on VLAN 100: 1.1.0.2, 1.1.0.3, 1.1.0.4

VLAN 101

IP address: 1.11.1/24

Subnet broadcast address: 1.1.1.255

Configured broadcast address: 1.1.255.255

Hosts on VLAN 100: 1.1.1.2, 1.1.1.3, 1.1.1.4

Packet 2

Switched Packet

TLV 1

Chassis ID

Preamble

Start Frame

Delimiter

Destination MAC

(01:80:C2:00:00:0E)

Source MAC

Ethernet Type

(0x88CC)

LLDPDU

Padding

FCS

TLV 2

Port ID

TLV 3

Port Description

TLV 4

System Name

TLV 5

System Description

TLV 6

System Capabilities

TLV 7

Management Addr

TLV 0

End of LLDPDU

TLV 127

Organizationally Specific