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

[Andrew Beekhof]

Needs some updates.


+	Scores of all kinds are integral to how a cluster works.

well, not all clusters, just pacemaker ones.
How about:

+	Scores of all kinds are integral to how Pacemaker clusters work.


Assume the intent was to avoid confusion with actual sets here?

-	  <title>Example set of opt-in location constraints</title>
+	  <title>Example of opt-in location constraints</title>

Prefer something like:
+	  <title>Example usage of opt-in location constraints</title>

or similar to indicate that they only make sense together.


I usually try to avoid questions as titles:
-	<title>What if Two Nodes Have the Same Score</title>
+	<title>What if Two Nodes Have the Same Score?</title>

How about:
+	<title>When Two Nodes Have the Same Score</title>


I like the existing text in this case
-      <title>Specifying the Order Resources Should Start/Stop In</title>
-      <para>The way to specify the order in which resources should
start is by creating <literal>rsc_order</literal> constraints.</para>
+      <title>Specifying Resource Start/Stop Order</title>
+      <para>Use a <literal>rsc_order</literal> constraint to specify
resource ordering.</para>

Also here:
-	      <entry>The name of a resource that must be started before the
then resource is allowed to. </entry>
+	      <entry>The name of a resource that must be started before the
then resource. </entry>
Although changing to be a literal would be an improvement.

Also think colocation makes more sense than resource here:
-		<entry>The colocation target. The cluster will decide where to put
this resource first and then decide where to put the resource in the
rsc field</entry>
+		<entry>The resource target. The cluster will decide where to put
this resource first and then decide where to put the colocation
resource specified in the rsc field</entry>

+      <para>Resource sets were introduced for ordering and dependency
contraints to simplify this situation.</para>
Prefer instead:
+      <para>To simplify the construction of ordering chains, the
resource set syntax may be used instead.</para>

+        Using resource sets for complex colocation contraints makes
things easier.
Prefer:
+      <para>To simplify the construction of colocation chains, the
resource set syntax may be used instead.</para>


nack, the word "equivalent" is important here
-	<title>The equivalent colocation chain expressed using resource_sets</title>
+	<title>A resource set for the same colocation dependency chain</title>

and here:
-	<title>A group resource with the equivalent colocation rules</title>
+	<title>A group resource for the same colocation dependency chain</title>


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.


Strictly speaking, they do have ordering dependancies, just not within the set.
+	    <caption>Visual representation of a colocation chain where the
members of the middle set have no order dependencies</caption>

Suggest:
+	    <caption>Visual representation of a colocation chain where the
members of the middle set have no ordering dependencies with the other
sets</caption>






On Mon, Mar 21, 2011 at 3:51 AM, Marcus Barrow <mbarrow at redhat.com> wrote:
>
> More simple changes for the "Pacemaker Explained" document. These are for CH_Constraints.xml and consist of typos and small changes. It also includes a change to Section 6.6 where dependency on preceding sets and preceding members of sets are described as M=1 and N+1. These were just changed to use the word preceding, which might be more clear.
>
> Regards,
> Marcus Barrow
>
>
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