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During an upgrade from NIOS 6.4.0 to a later release, you can revert a specific member that has already been upgraded and is within its revert time window. The revert single member feature is useful when you want to troubleshoot issues, such as service outages, on a specific member after it has been upgraded. You can revert a member only when the Grid upgrade is paused, and you cannot revert the Grid Master, reporting appliance, and an offline member. If the member you want to revert is upgrade is paused and you have reverted a member in an upgrade group that has already completed the upgrade, you must move the member to another upgrade group that has not been upgraded before you can proceed with the upgrade.
Once a member is upgraded, the appliance starts counting down and displays the time that is left for you to revert this member. You can revert the member before the revert time window expires. The default time window to revert a member is 24 hours. You can view the time that is left to revert the member in the Member List view, as described in Grid and Member Status . You can also use the CLI commands set default_revert_window to configure the default revert time window for the Grid. For information about this command, refer to the Infoblox CLI Guide. Once a member exits the revert time window, you must revert the entire Grid in order to revert the member.
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