6.0.1

Cluster Recommendations for Protecting vCenter Server
When conguring the vSphere HA and vSphere DRS cluster that you use to provide vCenter Server
availability by protecting the vCenter Server database server, observe these recommendations.
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Place all database servers in a dedicated management cluster.
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For vSphere DRS, create VM and host anti-anity rules to prevent the database servers from running
on the same host.
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Set the ForceAffinePoweron vSphere DRS advanced option to a value of 1 to enable strict enforcement
of vSphere DRS rules when servers are powered on.
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Enable vSphere HA with both host and VM monitoring.
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Enable and properly congure vSphere HA admission control for the cluster.
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Set the VM restart priority for the VM or VMs that are hosting the vCenter Server database to High.
Establishing Watchdog Support
Watchdog monitors and protects vCenter Server services. If any services fail, Watchdog aempts to restart
them. If it cannot restart the service because of a host failure, vSphere HA restarts the virtual machine (VM)
running the service on a new host.
Watchdog can provide beer availability by using vCenter Server processes (PID Watchdog) or the
vCenter Server API (API Watchdog).
You can use the service start command to start PID Watchdog and the service stop command to stop it. PID
Watchdog monitors only services that are running. After the service is stopped, PID Watchdog does not
monitor it. PID Watchdog detects only that a process with the correct executable is in the process table. It
does not determine if the process is ready to service requests.
Starting with vSphere 6.x, a Python daemon called API Watchdog checks the status of APIs for the VPXD
service. If the APIs are not running, API Watchdog aempts to restart the service two times. If that still does
not solve the issue, API Watchdog then reboots the VM.
API Watchdog starts running immediately after deployment of the vCenter Server Appliance. On
vCenter Server for Windows, however, you must reboot vCenter Server once before API Watchdog starts
working.
API Watchdog generates support bundles before a service restart and also before a VM reboot and these
support bundles are stored in C:\ProgramData\VMware\vCenterServer\data\core\*.tgz on vCenter Server
for Windows and in /storage/core/*.tgz for vCenter Server Appliance.
N To reset the Watchdog capability, delete the data les. On vCenter Server for Windows, the default
location is C:\ProgramData\VMware\vCenterServer\data\iiad\iiad.dat. On vCenter Server Appliance, it
is /storage /iiad/iiad.dat.
Using MSCS for vCenter Server Availability
With vCenter Server 5.5 Update 3 and later, Microsoft Cluster Service (MSCS) is supported as an option for
providing vCenter Server availability.
Multiple instances of vCenter Server are in a MSCS cluster, but only one instance is active at a time. Use this
solution to perform maintenance, such as patching or upgrades, on one node in the cluster without taking
down the vCenter Server database.
vCenter Server and Host Management
62 VMware, Inc.