- play_arrow Virtual Chassis Overview
- Virtual Chassis Overview for Switches
- Understanding EX Series Virtual Chassis
- Understanding QFX Series Virtual Chassis
- Understanding Virtual Chassis Components
- Understanding Mixed EX Series and QFX Series Virtual Chassis
- Understanding How the Primary in a Virtual Chassis Is Elected
- Understanding Global Management of a Virtual Chassis
- Understanding Virtual Chassis Port Link Aggregation
- Understanding Split and Merge in a Virtual Chassis
- Understanding Automatic Software Update on Virtual Chassis Member Switches
- Understanding MAC Address Assignment on a Virtual Chassis
- Understanding High Availability on an EX Series Virtual Chassis
- Understanding HiGig and HGoE Modes in a Virtual Chassis
- play_arrow Virtual Chassis Routine Monitoring and Troubleshooting
- Command Forwarding Usage with EX Series and QFX Series Virtual Chassis
- Verifying the Member ID, Role, and Neighbor Member Connections of a Virtual Chassis Member
- Verifying That Virtual Chassis Ports Are Operational
- Verifying That Graceful Routing Engine Switchover Is Working in the Virtual Chassis
- Troubleshooting an EX Series Virtual Chassis
- play_arrow Upgrading Software on a Virtual Chassis
- Understanding Software Upgrades in a Virtual Chassis
- Upgrading a QFX5100 Switch with a USB Device to Join a QFX5110 Virtual Chassis or Virtual Chassis Fabric
- Understanding Nonstop Software Upgrade on a Virtual Chassis and Mixed Virtual Chassis
- Configuring Line-Card Upgrade Groups for Nonstop Software Upgrade
- Upgrading Software on a Virtual Chassis and Mixed Virtual Chassis Using Nonstop Software Upgrade
- play_arrow Configuration Statements and Operational Commands
- play_arrow Knowledge Base
Disabling Split and Merge in a Virtual Chassis
The split and merge feature is enabled by default on all EX Series switches and QFX Series devices that are connected into a Virtual Chassis.
If a Virtual Chassis splits:
Each part detects the members they can still reach and elects a new primary for those members to form a smaller Virtual Chassis.
Each part determines if it will remain the active new configuration of the original Virtual Chassis. The feature’s rules ensure only one part remains active after a split.
See Understanding Split and Merge in a Virtual Chassis for complete details on what happens during a Virtual Chassis split or merge.
You can disable the split and merge feature in a Virtual Chassis by configuring the
no-split-detection option on the Virtual Chassis. In this case,
if the Virtual Chassis splits, both parts of the split Virtual Chassis configuration
usually remain active.
However, with split detection disabled, be aware that the two resulting Virtual Chassis might not form as you might expect. For example, in a preprovisioned Virtual Chassis:
If both of the Routing Engines end up in the same Virtual Chassis configuration after a split, the other part of the split Virtual Chassis configuration can’t form and remains inactive (because it has no members that can take on the primary or backup Routing Engine).
If the Routing Engines end up in different parts of the split Virtual Chassis configuration and the rest of the member switches are configured in linecard roles, then the resulting Virtual Chassis parts might not be able to select a backup Routing Engine.
We very strongly recommend that you:
Keep the default setting with the split and merge feature enabled for any Virtual Chassis with more than two members.
This provides the most predictable results when a split happens, and enables the split and merge feature to perform a merge after the issues that caused the split are resolved.
Disable split and merge on a Virtual Chassis with only two member switches by setting the
no-split-detectionoption.We have found that a two-member switch Virtual Chassis with split and merge disabled re-forms more quickly with fewer complications when a split occurs.
If you expand a two-member Virtual Chassis to include more members, delete the
no-split-detectionsetting to re-enable split and merge feature again.
To disable the split and merge feature in a Virtual Chassis:
[edit] user@switch# set virtual-chassis no-split-detection
To remove this configuration item to restore the default configuration with the split and merge feature again—we very strongly recommend that you do this when a two-member Virtual Chassis is expanded to have more members:
[edit] user@switch# delete virtual-chassis no-split-detection
