[Pacemaker] [pacemaker][patch 3/4] Simple changes for "Pacemaker Explained", Chapter 6 CH_Constraints.xml

Andrew Beekhof andrew at beekhof.net
Mon Apr 11 07:37:43 EDT 2011


On Mon, Apr 11, 2011 at 12:57 PM, Tim Serong <tserong at novell.com> wrote:
> On 3/21/2011 at 08:20 PM, Andrew Beekhof <andrew at beekhof.net> wrote:
>>
>> Small improvement to:
>> +     The only thing that matters is that in order for any member of a set
>> to be active, all the members of the previous set must also be active
>> (and naturally on the same node). When a set has
>> <literal>sequential="true"</literal>, then in order for any member to
>> be active, the previous members must also be active.
>>
>> +     The only thing that matters is that in order for any member of a set
>> to be active, all the members of the previous set<footnote><para>as
>> determined by the display order in the configuration</para></footnote>
>> must also be active (and naturally on the same node).
>> + When a set has <literal>sequential="true"</literal>, then in order
>> for any member to be active, the previous members must also be active.
>
> This isn't quite correct.
>
> For members within a set (sequential=true), it is true that for a given
> member to be active, the previous members must also be active.
>
> Between sets however, it's the other way around - a given set depends on
> the subsequent set.

Did I really write it like that? You tested it?
If so, thats just retarded and needs an overhaul.

>
> The example colocation chain in Pacemaker Explained right now should thus
> be changed as follows in order to match the diagram:
>
>  <constraints>
>    <rsc_colocation id="coloc-1" score="INFINITY" >
>       <resource_set id="collocated-set-1" sequential="true">
> -        <resource_ref id="A"/>
> -        <resource_ref id="B"/>
> +        <resource_ref id="F"/>
> +        <resource_ref id="G"/>
>      </resource_set>
>      <resource_set id="collocated-set-2" sequential="false">
>        <resource_ref id="C"/>
>        <resource_ref id="D"/>
>        <resource_ref id="E"/>
>      </resource_set>
>      <resource_set id="collocated-set-2" sequential="true" role="Master">
> -        <resource_ref id="F"/>
> -        <resource_ref id="G"/>
> +        <resource_ref id="A"/>
> +        <resource_ref id="B"/>
>      </resource_set>
>    </rsc_colocation>
>  </constraints>
>
> Regards,
>
> Tim
>
>
> --
> Tim Serong <tserong at novell.com>
> Senior Clustering Engineer, OPS Engineering, Novell Inc.
>
>
>
>
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