Delay Windows (member) Server start-up until Domain Controller is available

Question

What is the most efficient way do delay (or pause) the cold start-up of Windows domain member servers until a domain server is available? There are ways to delay the start-up of a server , but it is a bit inefficient, because there is no real need to delay the start-up if a domain controller is already available, but if a domain controller is not available it has a big impact on services that depend on the availability of a domain controller (most services fail to start if it depends on an unavailable domain controller and has to be started manually once the domain server is up an running).

Your questions is surprising because [all domains should have at least two functioning domain controllers for redundancy](https://technet.microsoft.com/en-us/library/dd378865%28v=ws.10%29.aspx?f=255&MSPPError=-2147217396). If both are down, you have more serious problems. If you use a Small Business Server, you should add the appropriate tag. — Daniel, Nov 25 '15 at 10:52
@Daniel It's not so surprising if you realize I'm from South Africa, and here we have more power failures than we can handle. Even longer than the UPS or generators can hold. So it happens allot that we have to start the server room (or network) from a cold start. So even if we had a backup Domain Controller (which we actually have 3 of) it wont help us much if you think about it (at least before you vote my question down). We are thinking of isolating the servers from the same power outlet, but it is easier said then done. So, I'm searching for a software based solution for now. — Francois Nel, Nov 25 '15 at 12:04
I think you should add that to the question because it's important to point out that your environment is in a healthy and supported state. — Daniel, Nov 25 '15 at 12:45

score 5 · Accepted Answer · edited Nov 27 '15 at 16:08

5

The easiest solution would be to activate WOL and run a startup script on the domain controller that sends the WOL magic packet to the other servers.

You would have to configure the BIOS/UEFI of the servers to

power up all domain controllers after a power failure when the power is restored, and
to keep all other servers powered off after a power failure, and
activate WOL.

edited Nov 27 '15 at 16:08

Francois Nel

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answered Nov 25 '15 at 12:54

Daniel

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Thanks! This gave me some ideas that could actually work. – Francois Nel Nov 27 '15 at 14:55

score 0 · Answer 2 · answered Nov 28 '15 at 21:41

Neat question. I just want to add an alternative for what it's worth. Daniel's question is fine; this is just my 2 cents.

This solution is highly-dependent on your hardware platform, (technically WOL is dependent on your hardware as well, but WOL is very widely implemented,) but let's just take HP servers as an example. HP servers typically have out-of-band management subsystems called ILOs (Integrated Lights-Out.) This subsystem should be automatically "On" as long as the server has power.

On your DC, you could attach a task to an event logged by the DC that indicates its "readiness," or you could perform some sort of manual health check in your script, such as by trying to bind to TCP ports 88, 389, etc. Once your script has determined that AD is healthy, you can use the HP ILO Powershell cmdlets to remotely power on the server like so:

Set-HPiLOHostPower -Server $MyServer `
                   -Username $IloUser `
                   -Password $IloPassword`
                   -HostPower "Yes"

Delay Windows (member) Server start-up until Domain Controller is available

2 Answers2