[Linux-cluster] How to configure resource dependency in service

[Lon Hohberger]

On Wed, 2007-10-24 at 12:00 -0400, Vlad Seagal wrote:
> Hi All,
> I’m trying to configure cluster service that would include the
> following resources:
> GFS, IP, script (webserver).
> <service autostart="1" domain="node1-fail" exclusive="0"
> name="webserver" recovery="restart">
>                         <clusterfs ref="GFS"/>
>                         <ip ref="10.17.123.226"/>
>                         <script ref="webserver"/>
>                 </service>
> 
> I put them into the service without any dependency and it works, but I
> need to have a control of which resource starts after which. 

Actually, since this is the most common dependency used by
customers/users, no matter what order you put those 3 resources in
cluster.conf as a child of the "service"...

> I need to have the following dependency: GFS -->IP-->webserver

... they will start in this order:
  
  (1) start fs/clusterfs
  (2) start ip
  (3) start script

... and stop in this order:

  (1) stop script
  (2) stop IP
  (3) stop fs/clusterfs

See:

  /usr/share/cluster/service.sh

The "child" start/stop levels control what classes of resources are
started before other classes of resources.  This specification (in
service.sh) only affects children of the "service" quasi-resource; other
resources may provide different start/stop orders, but usually they
don't.

-- Lon