Windows service dependency ONLY during startup

windowswindows-server-2008windows-service

I'm using windows server 2008 R2. When the server is rebooted, and only at this time, I need to ensure that service A starts, then service B, then service C.

I've researched dependencies, but as I understand it setting up service B to be dependent on service A and service C to be dependent on service B means that if A needed to be stopped, then B and C would also be stopped. I don't want that to happen. I only want the services to be dependent on each other when they are starting, but be able to stop them independent of each other.

I also looked at setting up a task schedule for stopping/starting the services, but the reboot times are not always scheduled so that doesn't seem appropriate, either.

Is it possible to have services be dependent on other services only when they are starting?

Best Answer

This is not possible; if ServiceA depends on ServiceB, a restart of ServiceB is guaranteed to force a restart on ServiceA. However, service dependancies can be changed programmatically; have a look into the sc command, especially the sc config depend= part.

Another viable option would be to set your services to manual mode, and then use a startup script (or a scheduled task configured to run at boot time) to launch them in the required order; this would still ensure the correct startup order, but without requiring explicit dependencies.

Examples

Dependency on one other service:

sc config ServiceA depend= ServiceB

Above means that ServiceA will not start until ServiceB has started. If you stop ServiceB, ServiceA will stop automatically.

Dependency on multiple other services:

sc config ServiceA depend= ServiceB/ServiceC/ServiceD/"Service Name With Spaces"

Above means that ServiceA will not start until ServiceB, ServiceC, and ServiceD have all started. If you stop any of ServiceB, ServiceC, or ServiceD, ServiceA will stop automatically.

To remove all dependencies:

sc config ServiceA depend= /

To list current dependencies:

sc qc ServiceA

Windows Service Limit Crashes Services on Startup

If your service is loading a copy of the message queuing driver (Mqac.sys) per instance, it's likely that you are running out of System View Space memory pool. Each instance of MSMQ uses 4MB of this pool and by default the pool size is only 16MB.

Whether this is actually happening will really depend on how (if at all) your service uses the MSMQ system, and whether it references it directly (loads its libraries) or uses some other method such as sockets to communicate with it.

If it turns out you are loading multiple instances of MSMQ you can mitigate your problem by increasing the system view space pool. This can be done by:

Open the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management.
Create a new DWORD value called SystemViewSize.
Calculate and specify this value as follows:
- Use this formula: (16 + (the number of Message Queuing resources loaded x 4)).
- For example, the value for a cluster with three Message Queuing resources equals 28.
Reboot