Hi,
I spent time to find out which vSphere features will stop working when vCenter goes down, but the received answers are not always the same.
I hope someone can help me to provide exactly what will happen? Do we need vCenter HA if we have FT feature enabled?
Will vMotion, FT, HA or DRS continuity function?
Thanks,
An
No FT/HA doesn't require vMotion to operate, where you read it.
vMotion means a VM's active CPU and RAM resources are migrated from one physical host to another. This is live migration when your VM is running.
HA - HA triggers when there's issue with physical host availability. HA restart VMs on another available host. Restart means > Power Off and register on another host, not migration active CPU and RAM (vmotion)
FT - In same way, when FT works because secondary VM is already running on secondary host, there's no need for migration. FT will make secondary VM available as primary.
Note : You need vCenter to be available to configure HA and FT first time. Once you configure, the VMs protected with FT and HA will operate under FT and HA policies either vCenter is available or not.
Do we need vCenter HA if we have FT feature enabled?
> Yes, HA must be enabled on Cluster before you enable FT on VMs.
Features available when vCenter is down :
Distributed Switch
High Availability
Fault Tolerance
Features not available when vCenter is down :
VMotion and SVMotion
DRS and Storage DRS
Central Management
Patching (Update Manager)
You can use High Availability for vCenter (VCSA 6.5) to avoid downtime.
Hi,
Thanks for your response.
As I know, FT/ HA requires vMotion for operation so how can it work without vMotion?
No FT/HA doesn't require vMotion to operate, where you read it.
vMotion means a VM's active CPU and RAM resources are migrated from one physical host to another. This is live migration when your VM is running.
HA - HA triggers when there's issue with physical host availability. HA restart VMs on another available host. Restart means > Power Off and register on another host, not migration active CPU and RAM (vmotion)
FT - In same way, when FT works because secondary VM is already running on secondary host, there's no need for migration. FT will make secondary VM available as primary.
Note : You need vCenter to be available to configure HA and FT first time. Once you configure, the VMs protected with FT and HA will operate under FT and HA policies either vCenter is available or not.
thank you so much, understood now
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