PCNS 4.4.3 for VMWare - Our setup does not correspond to any setup on Application Note 180

VT_IT · ‎2023-01-15

Dear community,

I’m currently in the process of installing PCNS in the below described environment, but cannot find any information on the “Application Note 180” regarding the sequence that would be triggered by a power event, as our setup does not correspond to any scenario on that note.

We have 2 sites, A and B, that are actually 2 server rooms in the same building. Each of those sites is protected by a single UPS (a Smart-UPS X 3000 in site A and a Smart-UPS 3000 in site B). We have 4 hosts with local storage on site A and 3 on site B. There is no SAN or storage array of any kind, the VM’s run on the local storage of the hosts. The PCNS VM is running in site B, as is the vCenter VM, and we have vSphere STD licenses.

What would be the behaviour of the PCNS and the sequence triggered in those cases :

UPS on battery = power failure on site A -> would the VM’s on site A be shut down gracefully, with no further action, as the vCenter and PCNS are on site B ? And no action would be taken on site B ?
UPS on battery = power failure on site B -> would the VM’s + vCenter + PCNS be shut down on site B, but the site A would remain untouched ?

Thanks in advance for your help

BillP · ‎2023-01-19

@VT_IT

UPS on battery = power failure on site A -> would the VM’s on site A be shut down gracefully, with no further action, as the vCenter and PCNS are on site B ? And no action would be taken on site B ? Correct. Site B would remain untouched and vCenter would remain up.
UPS on battery = power failure on site B -> would the VM’s + vCenter + PCNS be shut down on site B, but the site A would remain untouched ? Correct. Site A would remain untouched. Site B would be powered off along with vCenter.

To accomplish this, you should install two instances of PCNS. One on site A and one on site B. They both can be configured with the same vCenter. When selecting which hosts to power off you would only select the hosts per site.

In the screenshot above site one is protect by the PCNS instance. Site two is not, but it has its own instance of PCNS.

See Answer In Context

BillP · ‎2023-01-19

@VT_IT

UPS on battery = power failure on site A -> would the VM’s on site A be shut down gracefully, with no further action, as the vCenter and PCNS are on site B ? And no action would be taken on site B ? Correct. Site B would remain untouched and vCenter would remain up.
UPS on battery = power failure on site B -> would the VM’s + vCenter + PCNS be shut down on site B, but the site A would remain untouched ? Correct. Site A would remain untouched. Site B would be powered off along with vCenter.

To accomplish this, you should install two instances of PCNS. One on site A and one on site B. They both can be configured with the same vCenter. When selecting which hosts to power off you would only select the hosts per site.

In the screenshot above site one is protect by the PCNS instance. Site two is not, but it has its own instance of PCNS.

VT_IT · ‎2023-01-23

Hello BillP,

Many thanks for your efficiency ! Your answer has been quick and precise. I'll setup a second PCNS instance in the coming days. Have a nice week 🙂