[ClusterLabs] Default resource stickiness issue with colocation constraint

[Strahil Nikolov]

Hello All,

can someone help me figure something out.

I have a test cluster with 2 resource groups:

[root at node3 cluster]# pcs status
Cluster name: HACLUSTER16
Stack: corosync
Current DC: node3.localdomain (version 1.1.20-5.el7_7.2-3c4c782f70) - partition with quorum
Last updated: Sun Mar  8 20:00:48 2020
Last change: Sun Mar  8 20:00:04 2020 by root via cibadmin on node3.localdomain

3 nodes configured
14 resources configured

Node node2.localdomain: standby
Node node3.localdomain: standby
Online: [ node1.localdomain ]

Full list of resources:

 RHEVM  (stonith:fence_rhevm):  Started node1.localdomain
 MPATH  (stonith:fence_mpath):  Started node1.localdomain
 Resource Group: NFS
     NFS_LVM    (ocf::heartbeat:LVM):   Started node1.localdomain
     NFS_infodir        (ocf::heartbeat:Filesystem):    Started node1.localdomain
     NFS_data   (ocf::heartbeat:Filesystem):    Started node1.localdomain
     NFS_IP     (ocf::heartbeat:IPaddr2):       Started node1.localdomain
     NFS_SRV    (ocf::heartbeat:nfsserver):     Started node1.localdomain
     NFS_XPRT1  (ocf::heartbeat:exportfs):      Started node1.localdomain
     NFS_NTFY   (ocf::heartbeat:nfsnotify):     Started node1.localdomain
 Resource Group: APACHE
     APACHE_LVM (ocf::heartbeat:LVM):   Started node1.localdomain
     APACHE_cfg (ocf::heartbeat:Filesystem):    Started node1.localdomain
     APACHE_data        (ocf::heartbeat:Filesystem):    Started node1.localdomain
     APACHE_IP  (ocf::heartbeat:IPaddr2):       Started node1.localdomain
     APACHE_SRV (ocf::heartbeat:apache):        Started node1.localdomain

The constraints I have put are:

[root at node3 cluster]# pcs constraint
Location Constraints:
  Resource: APACHE
    Enabled on: node1.localdomain (score:3000)
    Enabled on: node2.localdomain (score:2000)
    Enabled on: node3.localdomain (score:1000)
  Resource: NFS
    Enabled on: node1.localdomain (score:1000)
    Enabled on: node2.localdomain (score:2000)
    Enabled on: node3.localdomain (score:3000)
Ordering Constraints:
Colocation Constraints:
  APACHE with NFS (score:-1000)
Ticket Constraints:

[root at node3 cluster]# pcs resource defaults
resource-stickiness=1000

As you can see the default stickiness is 1000 per resource or 7000 for the APACHE group.
The colocation rule score is just -1000 and as per my understanding it should be ignored when the 2 nodes are removed from standby.

Can someone clarify why the APACHE group is moved , when the resource stickiness score is higher than the colocation score.

I have attached a file with the crm_simulate output (the output is correct, when the standby is removed - the group is moved).

Best Regards,
Strahil Nikolov
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