At 10:15 PM 10/13/2005 -0500, you wrote:

I know about this because I got bitten by it. I realize it's working as designed, but I think the design bites. Intuition tells me that if you collocate by group, any node not in a group doesn't get collocated. But that's not the way it is.

--
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



>-----Original Message-----
>From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On
>Behalf Of Kolbeinn Jósepsson
>Sent: Thursday, October 13, 2005 9:22 PM
>To: ADSM-L AT VM.MARIST DOT EDU
>Subject: Re: Group collocation
>
>My apologizes, Mark you are correct!
>
>The best practise should be to use at least two seperate
>storagepools, the
>first with collocation=no (where all non-collocated nodes
>belongs to) and
>the second with collocation=group (where nodes in collocaton groups
>belongs), you can then chose if you use the second pool also for
>collocation by node (non grouped nodes) or if you add the
>third stgpool
>with collocation=node (and perhaps the fourth stgpool with
>collocation=filespace if your environment is "large enough").
>
>Best regards,
>Kolbeinn
>
>
>
>
>"Stapleton, Mark" <mark.stapleton AT BERBEE DOT COM>
>Sent by: "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
>14.10.2005 01:39
>Please respond to
>"ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
>
>
>To
>ADSM-L AT VM.MARIST DOT EDU
>cc
>
>Subject
>Re: Group collocation
>
>
>
>
>
>
>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 hsudden 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
>
>
>

Fred Johanson
ITSM Administrator
University of Chicago