[Pacemaker] Question on resources' dependency and failover

[Gianluca Cecchi]

Hello,
I'm using pacemaker 1.0.8 on rh el 5.5 x86 with clusterlabs repo.
Based on other posts on linux-ha I'm trying to configure a 2-nodes cluster
where one of the nodes is nfs-server and the other one is nfs-client of the
resource exported by the first one.

The main parts borrowed form the related threads are that I had to set
 these two constraints:

configure colocation nfsclient_not_on_nfs-group -inf: nfs-group nfsclient
configure order nfsclient_after_nfs-group inf: nfs-group nfsclient

It is all ok if both nodes are ok.
And I have nfs-server on node1 and nfs-client on node2.
I successfully configured ping resource for monitoring connectivity (thanks
again Vadym for the patience for that..).

At runtime I have:
Online: [ ha1 ha2 ]

Full list of resources:

SitoWeb (ocf::heartbeat:apache):        Started ha1
 Master/Slave Set: NfsData
     Masters: [ ha1 ]
     Slaves: [ ha2 ]
 Resource Group: nfs-group
     lv_drbd0   (ocf::heartbeat:LVM):   Started ha1
     ClusterIP  (ocf::heartbeat:IPaddr2): Started ha1
     NfsFS (ocf::heartbeat:Filesystem):    Started ha1
     nfssrv     (ocf::heartbeat:nfsserver):     Started ha1
nfsclient (ocf::heartbeat:Filesystem):    Started ha2
 Clone Set: cl-pinggw
     Started: [ ha1 ha2 ]

Migration summary:
* Node ha1:  pingd=200
* Node ha2:  pingd=200

and stickiness for cluster is set to 1000

I can successfully execute
crm resource move nfs-group
(and then after a bit unmove to have chance to get it back in the future)
so that the roles are correctly exchanged between the two nodes at the end
of the process.

But I can't do
crm resource move nfsclient
because this resource then stops, and the same for nfs-group and nothing
restarts
If I run
crm resource unmove nfsclient
then all restarts (with the same roles as before)

I can live with this... but I would expect only failure of movement of
nfs-client without impact for nfs-server

If I prevent node1 (nfs-server role at the moment) to reach the gw, I
correctly get the resources swapped (because nfs-client is not bound to the
ping constraint)

The complete failure of services with my case for movement of nfs-client
lets me make this general question:

Suppose I have group of resources named G1 and a resource named R2.
I define an order R2 after G1 and a colocation constraint of -inf so
that they run on different nodes (2 nodes overall).
At runtime I have G1 on node1 and R2 on node2, correctly.
I do a move of G1, so that I would have at the end G1 on node2 and R2 on
node1.

But suppose node1 doesn' t satisfy requirements for running R2 (for
example a file system without the mount point directory on node1).

What Is the expected behaviour:
- R2 stops correctly on node2
- G1 starts correctly on node2
- R2 then, based on constraint and order, tries to start on node1 but fails
end of the game with G1 still running or
- G1 too goes in stopped status, so that I now have both G1 and R2 stopped?

And the other case:
At runtime I have G1 on node1 and R2 on node2, correctly.
I do a move of R2, so that I would expect at the end G1 on node2 (based on
anti-location) and R2 on node1.
Is it expected to have as a result both G1 and R2 in stopped state?

Thanks for clarifications
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