Dell 7000 Series manual NSF Example

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Stacking Dell PowerConnect 7000 Series Switches

NSF Example 1

Assume Unit 1 is the stack manager and Unit 2 is the standby switch. The following scenarios illustrate how the network recovers when Unit 1 is powered down.

•With NSF disabled: Unit 2 takes over as manager with a cold restart and clears the hardware tables. The video stream stops on Hosts 2 and 3 for at least 30 seconds as the OSPF adjacency is rebuilt, multicast routes are relearned, and spanning tree reconverges.

•With NSF enabled: Unit 2 takes over as manager with a warm restart. OSPF graceful restart keeps the adjacency with Router 1 up and Router 1 continues to forward to the stack. There is no perceivable outage of the video stream through the stack.

NSF Example 2:

Assume Unit 2 is the stack manager and Unit 3 is the standby switch, and both ports are active on the LAG. In this scenario, NSF is enabled and the initiate failover command is used.

•Because the unit with the root port goes down, the stack stops forwarding until the spanning tree control plane comes back and places the link on Unit 3 in the forwarding state (about 3 seconds).

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Contents Dell Technical White Paper Stacking Dell PowerConnect Series SwitchesStacking Dell PowerConnect 7000 Series Switches Contents Applicability IntroductionStacking and Management Stacking and Redundancy Stacking and PerformanceDual Stacking Modules Configured in a Ring Power-Up Sequencing Considerations Mixing M6348 and PC7000 Series Switches in a StackConsole#boot auto-copy-sw allow-downgrade Initial Installation and Power-up of a Stack Selecting the Standby Unit Selecting the Master UnitUpdating the Firmware on a Stack Automatic UpdateManual Update FTP Creating a Separate Vlan for File DownloadsFrom the Switching Vlan Vlan Membership page, click Add Navigate to the Routing IP IP Interface Configuration Page Stacking Dell PowerConnect 7000 Series Switches Click Apply Adding a Stack Member with Minimal Interruption Removing a Stack Member with Minimal Interruption Master Failover Merging Two Operational StacksEffect of Master Failover on PoE Devices Failover Scenarios Stack Member FailoverScenario Stack Split Stack Split with Manager Failure Nonstop Forwarding Nonstop Forwarding Scenario Initiating a Warm Failover of the Manager UnitNonstop Forwarding Example Router NSF Scenario Configuration via CLIStack Switch Switch NSF Example Parameter Timing NSF Re-convergence TimingSmall Configuration Stacking CLI CommandsSummary Stacking Web Interface
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