Usage of switched rack PDU

[Anonymous user]

In one of the previous posts we concluded following about UPS shutdown behaviour:

UPS Goes on battery
PCNS shutsdown
UPS remains on battery
Utility power restored
UPS goes back online
PCNS clients remain down
No power interruption
Other equipment stays up, uninterrupted
PCNS clients need to be physically powered back on

Additional question that I have is if it is possible to use switched rack PDU to automatically boot up PCNS clients after utility power is restored.

Darko

[BillP]

Yes, I believe you can. If you get a switched rack PDU and cycle power to a(n) outlet(s), I believe it will achieve what you want. That will cycle power completely to the server(s), which as long as that BIOS is set appropriately as we discussed, it will turn back on.

I guess the only downfall is that you'd have to login and tell it which outlets to powercycle. The PDU has a command line interface but I am not sure if that could benefit you in that situation unless you make a script that you can send to the PDU to cycle certain outlets each time this type of scenario happens.

I'll attach the command line info to this post just incase.

[Anonymous user]

Thank you very much for reply.

I've checked commands and it looks like that still I have to manually cycle power to server (by typing command).

What I would like to achieve is that in described scenario servers boot up automatically.

As far as I understand PDU is connected to UPS, UPS is never shutdowned (in scenario it didnt shutdown as a result of power loss, only servers shutdown), how PDU will determine that it was power loss at all ?

Darko

[BillP · Accepted solution]

thats the issue - the PDU doesnt have the intelligence to figure that out. so you'd have to reboot everything on the PDU manually but i was thinking that if you had a 24 outlet PDU and wanted to reboot random outlets, you could run a script to the PDU when YOU know the power came back on.

so you'd have to see whats easier - either going into the PDU telnet or web interface and choosing a couple of options and then applying a reboot or running a script on the PDU to do that very same thing all in one shot but regardless, you will need to initiate one of these actions, the PDU cannot tell when the power goes out and comes back on.