Remediation is the process during which vSphere Lifecycle Manager applies patches, extensions, and upgrades to ESXi hosts. Remediation makes the selected vSphere objects compliant with the attached baselines and baseline groups.

vSphere Lifecycle Manager supports the remediation of ESXi hosts against patch, extension, and upgrade baselines.

You can initiate remediation manually or schedule a regular remediation task to run at a time that is convenient for you.

You can remediate a single ESXi host or a container object. You can initiate remediation at a folder, a cluster, or a data center level.
Note: If you initiate remediation for an object that contains clusters that use a single vSphere Lifecycle Manager image, remediation is not performed on those clusters.

If a vCenter Server instance is connected to other vCenter Server systems by a common vCenter Single Sign-On domain, you can remediate only the inventory objects managed by the vCenter Server system where the vSphere Lifecycle Manager instance that you use runs.

Orchestrated Upgrades of ESXi Hosts

You can use baseline groups to perform an orchestrated upgrade of the ESXi hosts in your environment. The baseline group might contain a single host upgrade baseline and multiple patch or extension baselines, or multiple patch and extension baselines. vSphere Lifecycle Manager first upgrades the hosts and then applies the patch or extension baselines. Because the upgrade runs first and patches are applicable to a specific host version, the orchestrated workflow ensures that no patches are lost during the upgrade.

Orchestrated upgrades can be performed at a host, cluster, folder, or a data center level.

Starting with vCenter Server 6.7 Update 2, you can select and work with multiple baselines instead of grouping them into a baseline group first.

Maintenance Mode

If the update requires it, hosts are put into maintenance mode before remediation. Virtual machines cannot run when a host is in maintenance mode. To ensure a consistent user experience, vCenter Server migrates the virtual machines to other hosts within the cluster before the host is put in maintenance mode. vCenter Server can migrate the virtual machines if the cluster is configured for vMotion and if VMware Distributed Resource Scheduler (DRS) and VMware Enhanced vMotion Compatibility (EVC) are enabled. However, EVC is not a prerequisite for vMotion. EVC guarantees that the CPUs of the hosts are compatible. For container objects or individual hosts that are not in a cluster, migration with vMotion cannot be performed.

To remediate vSphere objects, you must have the Remediate to Apply Patches, Extensions, and Upgrades privilege. For more information about managing users, groups, roles, and permissions, see the vSphere Security documentation.

For a list of all vSphere Lifecycle Manager privileges and their descriptions, see vSphere Lifecycle Manager Privileges For Using Baslines.

Remediation Pre-Check

Before you remediate an object, you can perform a remediation pre-check on the object. During that check, vSphere Lifecycle Manager identifies possible issues that might prevent successful remediation and suggests actions to fix the issues.

For more information about the possible issues that might prevent successful remediation, see Remediation Pre-Check Report.

Remediation of PXE Booted ESXi Hosts

vSphere Lifecycle Manager lets you remediate PXE booted ESXi hosts. vSphere Lifecycle Manager does not apply the patches that require a reboot to PXE booted ESXi hosts.

If there is any additional software installed on the PXE booted ESXi host, the software might be lost if the host restarts. Update your image profile with the additional software so that it will be present after the reboot.

To patch PXE booted ESXi hosts, you must enable the respective setting in the Edit Settings for Host Remediation dialog box, which you open from the Settings tab in the vSphere Lifecycle Manager home view.