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Dell W-7030 AOS 6.4.x User Guide - Page 664

AP Communication with Controllers, Client State Synchronization

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Figure 82 Redundancy with a Active-Backup Master Controller Pair When a VRRP instance is configured on the controller vlan, there would be no change in the VRRP state if the failover scenario was tested by shutting down the port or bringing down the vlan. The controller remains in the Master state and sends VRRP advertisements, which do not reach the peer controller. When the port is down, the peer controller becomes the Master. However, when the port on the previous master is enabled, it takes over the Master state. The peer controller moves out of the master state when the original master sends a higher priority advertisement, even when preemption is not enabled. The peer controller will not be preempted if the master controller crashes or reboots. AP Communication with Controllers The High Availability features work across Layer-3 networks, so there is no need for a direct Layer-2 connection between controllers in a high-availability group. When the AP first connects to its active controller, the active controller provides the IP address of a standby controller, and the AP attempts to establish a tunnel to the standby controller. If an AP fails to connect to the first standby controller, the active controller will select a new standby controller for that AP, and the AP will attempt to connect to that standby controller. An AP will failover to its backup controller if it fails to contact its active controller through regular heartbeats and keepalive messages, or if the user manually triggers a failover using the WebUI or CLI. High Availability for bridge mode is supported on Campus APs. In this mode, the controller sends ACL Names to the APs instead of the ACL IDs. These APs generate and maintain the mapping between the ACL Name and ACL Id . In the event of a failover the ACL Name is sent to the AP from the stand-by controller. Since AP maintains the mapping, the ACL Ids remain intact during a failover. Client State Synchronization Client state synchronization allows faster client reauthentication in the event of a controller failure by synchronizing PMK and Key cache entries between active and standby controllers. When you enable this feature, clients only need to perform a four-way key exchange to reconnect to the network (instead of performing a full authentication to the RADIUS server), dramatically shortening the time required for the client to reconnect. The following section of this document describes topologies, guidelines, and limitations for this feature. To view the procedure for enabling the client state synchronization feature, see Configuring High Availability. 664 | Increasing Network Uptime Through Redundancy and VRRP Dell Networking W-Series ArubaOS 6.4.x | User Guide

Section	Page
Contents	3
About this Guide	83
What's New In ArubaOS 6.4.x	83
Features Introduced in ArubaOS 6.4.3.0	83
Features Introduced in ArubaOS 6.4.2.5	89
Features Introduced in ArubaOS 6.4.2.4	89
Features Introduced in ArubaOS 6.4.2.3	90
Features Introduced in ArubaOS 6.4.2.0	90
Features Introduced in ArubaOS 6.4.1.0	92
Features Introduced in ArubaOS 6.4.0.0	95
Fundamentals	98
WebUI	98
CLI	99
Related Documents	99
Conventions	99
Contacting Dell	100
The Basic User-Centric Networks	101
Understanding Basic Deployment and Configuration Tasks	101
Deployment Scenario #1: Controller and APs on Same Subnet	101
Deployment Scenario #2: APs All on One Subnet Different from Controller Subnet	102
Deployment Scenario #3: APs on Multiple Different Subnets from Controllers	103
Configuring the Controller	104
Running Initial Setup	104
Connecting to the Controller after Initial Setup	105
W-7000 Series and W-7200 Series Controller	105
New Port Numbering Scheme	105
W-7200 Series Controllers Individual Port Behavior	106
Using the LCD Screen	106
Using the LCD and USB Drive	108
Upgrading an Image	108
Uploading a Pre-saved Configuration	108
Disabling LCD Menu Functions	109
Configuring a VLAN to Connect to the Network	109
Creating, Updating, and Viewing VLANs and Associated IDs	110
Creating, Updating, and Deleting VLAN Pools	110
Assigning and Configuring the Trunk Port	110
In the WebUI	110
In the CLI	111
Configuring the Default Gateway	111
In the WebUI	111
In the CLI	111
Configuring the Loopback IP Address for the Controller	111
In the WebUI	112
In the CLI	112
Configuring the System Clock	112
Installing Licenses	112
Connecting the Controller to the Network	112
Enabling Wireless Connectivity	113
Enabling Wireless Connectivity	113
Configuring Your User-Centric Network	113
Replacing a Controller	114
Transferring Licenses	114
Procedure Overview	114
Change the VRRP Priorities for a Redundant Master Pair	115
Back Up the Flash File System	115
In the WebUI	115
In the CLI	115
Stage the New Controller	115
Add Licenses to the New Controller	116
Backup Newly Installed Licenses	116
Import and Restore Flash Backup	116
In the WebUI	117
In the CLI	117
Restore Licenses	117
Reboot the Controller	117
Modify the Host Name	118
Modify Topology Settings	118
Save your Configuration	119
Remove the Existing Controller	119
Control Plane Security	120
Control Plane Security Overview	120
Configuring Control Plane Security	121
In the WebUI	121
In the CLI	123
Managing AP Whitelists	123
Adding an AP to the Campus or Remote AP Whitelists	123
In the WebUI	123
In the CLI	125
Viewing AP Whitelist Status	125
Modifying an AP in the Campus AP Whitelist	128
In the WebUI	128
In the CLI	128
Revoking an AP from the Campus AP Whitelist	129
In the WebUI	129
In the CLI	129
Deleting an AP from the Campus AP Whitelist	129
In the WebUI	129
In the CLI	130
Purging a Campus AP Whitelist	130
In the WebUI	130
In the CLI	130
Offloading a Controller Whitelist to ClearPass Policy Manager	130
In the WebUI	130
In the CLI	131
Managing Whitelists on Master and Local Controllers	131
Campus AP Whitelist Synchronization	132
Viewing the Master or Local Controller Whitelists	133
In the WebUI	133
In the CLI	134
Deleting an Entry from the Master or Local Controller Whitelist	134
In the WebUI	134
In the CLI	134
Purging the Master or Local Controller Whitelist	135
In the WebUI	135
In the CLI	135
Working in Environments with Multiple Master Controllers	135
Configuring Networks with a Backup Master Controller	135
Configuring Networks with Clusters of Master Controllers	135
Creating a Cluster Root	136
Creating a Cluster Member	137
Viewing Controller Cluster Setting	137
Replacing a Controller on a Multi-Controller Network	138
Replacing Controllers in a Single Master Network	138
Replacing a Local Controller	138
Replacing a Master Controller with No Backup	139
Replacing a Redundant Master Controller	140
Replacing Controllers in a Multi-Master Network	140
Replacing a Local Controller in a Multi-Master Network	140
Replacing a Cluster Member Controller with no Backup	140
Replacing a Redundant Cluster Member Controller	141
Replacing a Cluster Root Controller with no Backup Controller	141
Replacing a Redundant Cluster Root Controller	142
Configuring Control Plane Security after Upgrading	142
Troubleshooting Control Plane Security	143
Identifying Certificate Problems	143
Verifying Certificates	144
Disabling Control Plane Security	144
Verifying Whitelist Synchronization	144
Rogue APs	145
Software Licenses	146
Understanding License Terminology	146
Working with Licenses	147
Centralized Licensing in a Multi-Controller Network	148
Primary and Backup Licensing Servers	149
Communication between the License Server and License Clients	149
Supported Topologies	151
Unsupported Topologies	152
Adding and Deleting Licenses	153
Replacing a Controller	153
Failover Behaviors	153
Client is Unreachable	154
Server is Unreachable	154
Configuring Centralized Licensing	154
Pre-configuration Setup in an All-Master Deployment	154
Preconfiguration Setup in a Master/Local Topology	155
Enabling Centralized Licensing	155
Monitoring and Managing Centralized Licenses	156
License server Table	156
License Client Table	156
License Client(s) Usage Table	157
Aggregate License Table	158
License Heartbeat Table	158
Using Licenses	158
Understanding License Interaction	160
License Installation Best Practices and Exceptions	160
Installing a License	161
Enabling a New License on your Controller	161
Requesting a Software License in Email	161
Locating the System Serial Number	161
Obtaining a Software License Key	162
Creating a Software License Key	162
Applying the Software License Key in the WebUI	162
Applying the Software License Key in the License Wizard	162
Deleting a License	162
Moving Licenses	163
Resetting the Controller	163
Network Configuration Parameters	164
Configuring VLANs	164
Creating and Updating VLANs	164
In the WebUI	164
In the CLI	165
Creating Bulk VLANs In the WebUI	165
In the CLI	165
Creating a Named VLAN	165
In the WebUI	165
Distinguishing Between Even and Hash Assignment Types	166
Updating a Named VLAN	166
Deleting a Named VLAN	166
Creating a Named VLAN Using the CLI	167
Viewing and Adding VLAN IDs Using the CLI	167
Role Derivation for Named VLAN Pools	167
In the CLI	167
In the WebUI	168
Adding a Bandwidth Contract to the VLAN	168
Optimizing VLAN Broadcast and Multicast Traffic	168
In the WebUI	168
In the CLI	169
Configuring Ports	169
Classifying Traffic as Trusted or Untrusted	169
About Trusted and Untrusted Physical Ports	169
About Trusted and Untrusted VLANs	169
Configuring Trusted/Untrusted Ports and VLANs	170
In the WebUI	170
In the CLI	170
Configuring Trusted and Untrusted Ports and VLANs in Trunk Mode	171
In the WebUI	171
In the CLI	171
Understanding VLAN Assignments	171
VLAN Derivation Priorities for VLAN types	172
How a VLAN Obtains an IP Address	173
Assigning a Static Address to a VLAN	173
In the WebUI	173
In the CLI	173
Configuring a VLAN to Receive a Dynamic Address	173
Configuring Multiple Wired Uplink Interfaces (Active-Standby)	173
Enabling the DHCP Client	174
In the WebUI	174
In the CLI	174
Enabling the PPPoE Client	175
In the WebUI	175
In the CLI	175
Default Gateway from DHCP/PPPoE	175
In the WebUI	175
In the CLI	175
Configuring DNS/WINS Server from DHPC/PPPoE	175
In the WebUI	175
In the CLI	176
Configuring Source NAT to Dynamic VLAN Address	176
In the WebUI	176
In the CLI	176
Configuring Source NAT for VLAN Interfaces	177
Sample Configuration	177
In the WebUI	177
In the CLI	177
Inter-VLAN Routing	178
In the WebUI	178
In the CLI	179
Configuring Static Routes	179
In the WebUI	179
In the CLI	179
Configuring the Loopback IP Address	179
In the WebUI	179
In the CLI	180
Configuring the Controller IP Address	180
In the WebUI	180
In the CLI	181
Configuring GRE Tunnels	181
About Layer-2 GRE Tunnels	181
Layer-2 GRE Tunnel Network Diagram	181
Layer-2 Traffic Flow	181
About Layer-3 GRE Tunnels	182
IPv4 Layer-3 GRE Tunnel Network Diagram	182
IPv6 Layer-3 GRE Tunnel Network Diagram	182
Layer-3 Traffic Flow	182
Configuring a Layer-2 GRE Tunnel	183
In the WebUI	183
In the CLI	185
Configuring a Layer-3 GRE Tunnel for IPv4	186
In the WebUI	186
In the CLI	187
Configuring a Layer-3 GRE Tunnel for IPv6	188
In the WebUI	188
In the CLI	189
Limitations for Static IPv6 Layer-3 Tunnels	190
Directing Traffic into the Tunnel	190
About Configuring Static Routes	190
Configuring a Firewall Policy Rule	190
Configuring Tunnel Keepalives	192
Configuring GRE Tunnel Groups	193
About GRE Tunnel Groups	193
Tunnel Group Order	193
Tunnel Failover	193
Preemption	194
Enabling a Tunnel Group	194
Points to Remember	194
Regarding Layer-2 Tunnel Groups	194
Configuring a Layer-2 or Layer-3 Tunnel Group Using the CLI	194
Example Configuration	194
Enabling Preemption	194
Viewing Operational Status	195
Viewing Active and Member Tunnels	195
Viewing the Standby Member Tunnels	195
Configuring a Layer-2 or Layer-3 Tunnel Group Using the WebUI	196
Jumbo Frame Support	196
Limitations for Jumbo Frame Support	196
Configuring Jumbo Frame Support	197
In the WebUI	197
In the CLI	197
Viewing the Jumbo Frame Support Status	197
IPv6 Support	198
Understanding IPv6 Notation	198
Understanding IPv6 Topology	198
Enabling IPv6	199
Enabling IPv6 Support for Controller and APs	199
Configuring IPv6 Addresses	201
In the WebUI	202
In the CLI	202
Configuring IPv6 Static Neighbors	202
In the WebUI	203
In the CLI	203
Configuring IPv6 Default Gateway and Static IPv6 Routes	203
In the WebUI	203
In the CLI	203
Managing Controller IP Addresses	203
In the WebUI	203
In the CLI	204
Configuring Multicast Listener Discovery	204
In the WebUI	204
In the CLI	205
Dynamic Multicast Optimization	205
In the WebUI	205
In the CLI	206
Limitations	206
Debugging an IPv6 Controller	206
In the WebUI	206
In the CLI	206
Provisioning an IPv6 AP	206
In the WebUI	207
In the CLI	207
Enhancements to IPv6 Support on AP	207
Filtering an IPv6 Extension Header (EH)	207
Configuring a Captive Portal over IPv6	207
Working with IPv6 Router Advertisements (RAs)	208
Configuring an IPv6 RA on a VLAN	208
Using WebUI	209
Using CLI	209
Configuring Optional Parameters for RAs	209
In the WebUI	210
In the CLI	211
RADIUS Over IPv6	211
In the CLI	211
In the WebUI	212
TACACS Over IPv6	212
In the CLI	212
In the WebUI	213
DHCPv6 Server	213
Points to Remember	213
DHCP Lease Limit	213
Configuring DHCPv6 Server	214
In the WebUI	214
In the CLI	215
Understanding ArubaOS Supported Network Configuration for IPv6 Clients	216
Supported Network Configuration	216
Understanding the Network Connection Sequence for Windows IPv6 Clients	216
Understanding ArubaOS Authentication and Firewall Features that Support IPv6	217
Understanding Authentication	217
Working with Firewall Features	217
Understanding Firewall Policies	219
Creating an IPv6 Firewall Policy	221
Assigning an IPv6 Policy to a User Role	222
Understanding DHCPv6 Passthrough/Relay	222
Managing IPv6 User Addresses	222
Viewing or Deleting User Entries	222
Understanding User Roles	223
Viewing Datapath Statistics for IPv6 Sessions	223
Understanding IPv6 Exceptions and Best Practices	223
Link Aggregation Control Protocol	225
Understanding LACP Best Practices and Exceptions	225
Configuring LACP	226
In the CLI	226
In the WebUI	227
LACP Sample Configuration	227
OSPFv2	229
Understanding OSPF Deployment Best Practices and Exceptions	229
Understanding OSPFv2 by Example using a WLAN Scenario	230
WLAN Topology	230
WLAN Routing Table	230
Understanding OSPFv2 by Example using a Branch Scenario	231
Branch Topology	231
Branch Routing Table	232
Configuring OSPF	232
Exporting VPN Client Addresses to OSPF	234
In the WebUI	234
In the CLI	234
Sample Topology and Configuration	234
Remote Branch 1	235
Remote Branch 2	236
W-3200 Central Office Controller—Active	237
W-3200 Central Office Controller—Backup	238
Topology	240
Observation	240
Configuring W-3600-UP Controller	240
Configuring W-3600-DOWN Controller	242
Viewing the Status of Instant AP VPN	243
RAPNG AP-1	243
RAPNG AP-3	244
Tunneled Nodes	246
Understanding Tunneled Node Configuration	246
Configuring a Wired Tunneled Node Client	247
Configuring an Access Port as a Tunneled Node Port	248
Configuring a Trunk Port as a Tunneled Node Port	248
Authentication Servers	249
Understanding Authentication Server Best Practices and Exceptions	249
Understanding Servers and Server Groups	249
Configuring Authentication Servers	250
Configuring a RADIUS Server	250
Using the WebUI	251
Using the CLI	251
RADIUS Service-Type Attribute	253
Enabling Radsec on RADIUS Servers	254
In the Web UI	254
In the CLI	254
RADIUS Server VSAs	254
RADIUS Server Authentication Codes	257
RADIUS Server Fully Qualified Domain Names	258
DNS Query Intervals	258
Configuring Username and Password for CPPM Authentication	258
In the WebUI:	258
In the CLI:	259
Configuring an RFC-3576 RADIUS Server	259
Using the WebUI	259
Using the CLI	259
Configuring an RFC-3576 RADIUS Server with Radsec	260
Using the WebUI	260
Using the CLI	260
Configuring an LDAP Server	260
Using the WebUI	261
Using the CLI	261
Configuring a TACACS+ Server	261
Using the WebUI	262
Using the CLI	262
Configuring a Windows Server	263
Using the WebUI	263
Using the CLI	263
Managing the Internal Database	263
Configuring the Internal Database	263
Using the WebUI	264
Using the CLI	264
Managing Internal Database Files	265
Exporting Files in the WebUI	265
Importing Files in the WebUI	265
Exporting and Importing Files in the CLI	265
Working with Internal Database Utilities	265
Deleting All Users	265
Repairing the Internal Database	265
Configuring Server Groups	266
Configuring Server Groups	266
Using the WebUI	266
Using the CLI	266
Configuring Server List Order and Fail-Through	266
Using the WebUI	267
Using the CLI	267
Configuring Dynamic Server Selection	267
Using the WebUI	268
Using the CLI	269
Configuring Match FQDN Option	269
Using the WebUI	269
Using the CLI	269
Trimming Domain Information from Requests	269
Using the WebUI	270
Using the CLI	270
Configuring Server-Derivation Rules	270
Using the WebUI	271
Using the CLI	272
Configuring a Role Derivation Rule for the Internal Database	272
Using the WebUI	272
Using the CLI	272
Assigning Server Groups	272
User Authentication	273
Management Authentication	273
Using the WebUI	273
Using the CLI	273
Accounting	273
RADIUS Accounting	273
RADIUS Accounting on Multiple Servers	276
TACACS+ Accounting	276
Configuring Authentication Timers	276
Setting an Authentication Timer	277
Using the WebUI	277
Using the CLI	278
Authentication Server Load Balancing	278
Enabling Authentication Server Load Balancing Functionality	278
MAC-based Authentication	279
Configuring MAC-Based Authentication	279
Configuring the MAC Authentication Profile	279
In the WebUI	280
In the CLI	280
Configuring Clients	280
In the WebUI	281
In the CLI	281
Branch Controller Config for Controllers	282
Branch Deployment Features	283
WAN Failure (Authentication) Survivability	284
Supported Client and Authentication Types	284
Supported Key Reply Attributes	285
Support Restrictions	285
Administrative Functions	285
Enabling Authentication Survivability on a Local Branch Controller	286
Configuring the Survival Server Certificate	286
Configuring the Lifetime of the Authentication Survivability Cache	286
User Credential and Key Reply Attributes Are Saved Automatically	286
Expired User Credential and Key Reply Attributes Are Purged Automatically	286
About the Survival Server	286
Trigger Conditions for Critical Actions	286
Storing User Access Credential and Key Reply Attributes to Survival Cache	286
Picking Up the Survival Server for Authentication	287
Access Credential Data Stored	287
Authentication for Captive Portal Clients	287
Captive Portal Client Authentication Using PAP	287
External Captive Portal Client Authentication Using the XML-API	287
Authentication for 802.1X Clients	288
802.1X Termination Disabled at the Wireless LAN Controller	288
802.1X Termination Enabled at the Wireless LAN Controller	288
Authentication for MAC Address-Based Clients	289
Authentication for WISPr Clients	289
WAN Health Check	290
WAN Optimization through IP Payload Compression	290
Distributed Layer 3 Branch Deployment Model	291
Compression/Decompression Engine	291
Modes of Operation	291

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664

| Increasing Network Uptime Through Redundancy and VRRP

Dell Networking W-Series ArubaOS 6.4.x | User Guide

Figure 82

Redundancy with a Active-Backup Master Controller Pair

When a VRRP instance is configured on the controller vlan, there would be no change in the VRRP state if the failover

scenario was tested by shutting down the port or bringing down the vlan. The controller remains in the Master state

and sends VRRP advertisements, which do not reach the peer controller. When the port is down, the peer controller

becomes the Master. However, when the port on the previous master is enabled, it takes over the Master state. The

peer controller moves out of the master state when the original master sends a higher priority advertisement, even

when preemption is not enabled. The peer controller will not be preempted if the master controller crashes or

reboots.

AP Communication with Controllers

The High Availability features work across Layer-3 networks, so there is no need for a direct Layer-2 connection

between controllers in a high-availability group.

When the AP first connects to its active controller, the active controller provides the IP address of a standby

controller, and the AP attempts to establish a tunnel to the standby controller. If an AP fails to connect to the

first standby controller, the active controller will select a new standby controller for that AP, and the AP will

attempt to connect to that standby controller.

An AP will failover to its backup controller if it fails to contact its active controller through regular heartbeats

and keepalive messages, or if the user manually triggers a failover using the WebUI or CLI.

High Availability for bridge mode is supported on Campus APs. In this mode, the controller sends ACL Names

to the APs instead of the ACL IDs. These APs generate and maintain the mapping between the ACL Name and

ACL Id . In the event of a failover the ACL Name is sent to the AP from the stand-by controller. Since AP

maintains the mapping, the ACL Ids remain intact during a failover.

Client State Synchronization

Client state synchronization allows faster client reauthentication in the event of a controller failure by

synchronizing PMK and Key cache entries between active and standby controllers. When you enable this

feature, clients only need to perform a four-way key exchange to reconnect to the network (instead of

performing a full authentication to the RADIUS server), dramatically shortening the time required for the client

to reconnect.

The following section of this document describes topologies, guidelines, and limitations for this feature. To view the

procedure for enabling the client state synchronization feature, see

Configuring

High

Availability