[Pacemaker] Dependency Trees

[Donald Stahl]

> On the one hand, you say OraListener1 and OraInstance1 need to be on
> the same node, but on the other you say they can start/stop
> individually.

There are maintenance reasons for some of these requirements- for
example the listener can only ever be on the same box as the database,
but I might want to take the listener down but keep the database up. I
realize it's an odd requirement.

> I hadn't read that part so closely when I said "shouldn't be too hard"
> and indeed that is hard for us to express.
> In Pacemaker, either A needs B or it doesn't.
Fair enough. I'm not the database guy so I've been asked to replicate
this VCS configuration as closely as possible. At the same time- I
want to understand pacemaker as well as I can. I appreciate your
feedback.

> Other than that, you seem to want:
>
> order OraInstance1 OraBin1
> order OraInstance1 OraData1
>
> order OraListener1 OraBin1
> order OraListener1 OraData1
> order OraListener1 OraIP1
>
> Do OraInstance1/OraListener1 need to live on the same host as OraBin1/OraData1 ?
> If so, you can get the behaviour you're after by adding something like:
>
> colocate OraInstance1 OraBin1
> colocate OraListener1 OraBin1
> colocate OraBin1 OraData1
>
> So OraInstance1 and OraListener1 can go up/down individually but
> always on the same host as OraBin1/OraData1.
> Also, if OraBin1 or OraData1 go down they'll take OraInstance1 and
> OraListener1 with them.
>
> Is that close?
That is exactly what I am trying to accomplish. I started to think
along those lines after your previous email (and doing a little more
reading) but I hadn't gotten there.

The only part I'm not clear on is - doesn't:
> colocate OraListener1 OraBin1

imply:
> order OraListener1 OraBin1
?

Or to put it another way- I'm not sure I understand the difference between:
colocate OraListener1 OraBin1

and:
colocate (OraListener1 OraBin1)
order OraListener1 OraBin1
?

Regardless of the answer- I should be able to get the config set up
the way I need. Thanks again for all of the help.

-Don