Knight, Doug wrote:
> OK, here's another strange happening, I had an IPaddr resource with a
> separate (non-WAL file forwarding instance) database co-located to it. I
> created this early on to get up to speed on the HA basics. It uses the
> heartbeat ocf script, as does IPaddr. I used a places constraint with a
> uname eq to move it manually between nodes in the cluster. As I was
> testing my multistate OCF script for the WAL file forwarding version, I
> decided to try moving the IPaddr resource from one node to another (I've
> been having some issues in my fail-over testing, so I thought I'd verify
> that the IPaddr handling still worked). When the IPaddr moved, it
> affected the WAL file forwarding resource as well. I haven't dug into
> the logs yet to see what happened, but the question becomes why would
> other resources on a node be affected when a change is made to a
> completely independent resource? Does it have something to do with
> managing everything from the GUI? Or making changes to the cib.xml
> (which I only do through the GUI right now)? I've also noticed that the
> monitoring of the resources does not appear to be happening. I killed
> the master database using the original LSB script and waited for the HA
> resource monitoring to pick it up and restart, but it didn't. I'm
> probably missing something simple here...
The CRM doesn't like to run resources on the same node if it can help it.
I don't know if this is your problem, but the CRM will decide to do
things for reasons not obvious unless you know the algorithms in detail.
I have definitely seen it do things like move a resource to another
place just as good as the place it was in for no reason motivated by the
contents of the CIB - only by the way the code is written.
[In this particular case I know of, it located a resource on node A
because A was first in the membership. A went away, and it moved to B.
When A came back, it thought the resource belonged "better" on A than
on B. There was no scoring difference between A and B, but it appeared
that since A came first on the list, it moved it back to A]
I can't say that I find apparently-random movements very comforting. In
fact they can be very costly. But Andrew already knows I think that.
I don't expect it to locate every resource where I think it could, but
it seems to me that it needs to have a reason (like score differential)
for it to move something.
The GUI is probably not your problem, although it could be. Seeing your
CIB before and after this change would be helpful. You could run it
through ptest and see what it thinks needs to be done.
--
Alan Robertson <[EMAIL PROTECTED]>
"Openness is the foundation and preservative of friendship... Let me
claim from you at all times your undisguised opinions." - William
Wilberforce
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