VMware Cloud Community
vijayreddy0315
Contributor
Contributor

Query in HA

Hi All,

I have Query on Highh Availability, There is culster and 3 ESXIS are configured. One of the Host is done, So all the VMs which are lying in that moved other Host.  Now I am query is: HA will create New VMs with the help of their VMDK files residing in the storage? If yes, if the Failure host is back to online will those VMS move back to old ESXI server? Explain me how this excatly work.

Thanks in Advance.

5 Replies
scott28tt
VMware Employee
VMware Employee

Moderator note: Technical questions should be posted in the forum area related to the technology/product - moving this thread from VCP to the HA & FT area.


-------------------------------------------------------------------------------------------------------------------------------------------------------------

Although I am a VMware employee I contribute to VMware Communities voluntarily (ie. not in any official capacity)
VMware Training & Certification blog
Reply
0 Kudos
scott28tt
VMware Employee
VMware Employee

To answer your question - have a look here: vSphere High Availability (HA) Technical Deepdive - Yellow Bricks


-------------------------------------------------------------------------------------------------------------------------------------------------------------

Although I am a VMware employee I contribute to VMware Communities voluntarily (ie. not in any official capacity)
VMware Training & Certification blog
linotelera
Hot Shot
Hot Shot

Hi... I'm trying to answer:

- HA restarts VM from failed to host to other available hosts but with some requirements, like shared storage (vmdk is not changing during failing over) and available resources (CPU/MEM) to other hosts

- After a host fail HA will only start VM.. but never failback... to acheive this you should configure another component (not included in essential plus license) which is called DRS

- You could find further information in the official doc: Help - vSphere 6.0 Documentation Center

Lino

vijayreddy0315
Contributor
Contributor

Thanks Lino....

Reply
0 Kudos
depping
Leadership
Leadership

you can find all details in my free book here: go to yellow-bricks.com and click the HA Deepdive. Now, one thing to note is that we do not reconstruct VMs, all needed components are already there, we just need to restart the VMs using the "VMX" file which is the VM configuration file, which by itself contains details around memory / cpu and disk. If you have DRS then DRS will balance the cluster automatically within 5 minutes after a failover. If you do not have DRS then you will need to do this manually.