Zoltan Forray/AC/VCU <zforray AT VCU DOT EDU>
>If I take a storage pool and change it to GROUP from NO 
>collocation, what
>about the data for nodes that ARE NOT in collocation groups ?  
>Does their
>data get collocated or not ?  Will I all of a sudden go from 1-2 daily
>LTO2 mounts to 30 ?

From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On 
Behalf Of Kolbeinn Jósepsson
>Only data from nodes in collocationgroup will be collocated, data from
>other nodes in same stgpool will not be collocated.

This is incorrect. My experience has been that, when setting a pool to 
"collocation by group", that any node not belonging to a collocation group will 
get its data to that pool collocated.

(from page 312 of the TSM 5.3 for Windows Administrators' Reference)
====
GRoup 
Specifies that collocation is enabled at the group level for client nodes. The 
server attempts to put data for nodes that belong to the same collocation group 
on as few volumes as possible. If the nodes in the collocation group have 
multiple file spaces, the server does not attempt to collocate those file 
spaces. 

If you specify COLLOCATE=GROUP but do not define any groups, data is collocated 
by node. Similarly, if you specify COLLOCATE=GROUP and you define a group but 
do not add nodes to the group, data is collocated by node.
===

The workaround I found is to create collocation groups and populate them, then 
create one more collocation group that contains all other nodes that write to 
that storage pool that are *not* already in a group.

--
Mark Stapleton (stapleton AT berbee DOT com)
IBM Certified Advanced Deployment Professional
 Tivoli Storage Management Solutions 2005
IBM Certified Advanced Technical Expert (CATE) AIX
Berbee Information Networks
Office 262.521.5627