2
# AUTHOR <EMAIL@ADDRESS>, YEAR.
6
"Project-Id-Version: 0\n"
7
"POT-Creation-Date: 2012-10-17T05:19:02\n"
8
"PO-Revision-Date: 2011-05-03 15:38+0100\n"
9
"Last-Translator: RaSca <rasca@miamammausalinux.org>\n"
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"Language-Team: None\n"
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"Content-Type: text/plain; charset=UTF-8\n"
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"Content-Transfer-Encoding: 8bit\n"
18
msgid "Resource Constraints"
19
msgstr "Vincoli delle risorse"
23
msgid "<indexterm> <primary>Resource</primary><secondary>Constraints</secondary> </indexterm> <indexterm> <primary>Constraints</primary> </indexterm>"
33
msgid "Scores of all kinds are integral to how the cluster works. Practically everything from moving a resource to deciding which resource to stop in a degraded cluster is achieved by manipulating scores in some way."
34
msgstr "Nel funzionamento del cluster sono integrati punteggi di ogni tipo. Praticamente qualsiasi decisione, dallo spostamento di una risorsa sino a quale risorsa fermare in un cluster degradato, è ottenuta manipolando in qualche forma i punteggi."
38
msgid "Scores are calculated on a per-resource basis and any node with a negative score for a resource can’t run that resource. After calculating the scores for a resource, the cluster then chooses the node with the highest one."
39
msgstr "I punteggi sono calcolati sulla base per l'erogazione di ogni risorsa e qualsiasi nodo con un punteggio negativo non può erogare la risorsa associata. Dopo aver calcolato i punteggi per una risorsa il cluster sceglie il nodo con il punteggio più alto."
44
msgstr "Il valore INFINITY"
48
msgid "<literal>INFINITY</literal> is currently defined as 1,000,000 and addition/subtraction with it follows these three basic rules:"
49
msgstr "<literal>INFINITY</literal> viene attualmente definito come 1,000,000 ed addizioni/sottrazioni ad esso seguono queste 3 regole base:"
53
msgid "Any value + <literal>INFINITY</literal> = <literal>INFINITY</literal>"
54
msgstr "Qualsiasi valore + <literal>INFINITY</literal> = <literal>INFINITY</literal>"
58
msgid "Any value - <literal>INFINITY</literal> = -<literal>INFINITY</literal>"
59
msgstr "Qualsiasi valore - <literal>INFINITY</literal> = -<literal>INFINITY</literal>"
63
msgid "<literal>INFINITY</literal> - <literal>INFINITY</literal> = -<literal>INFINITY</literal>"
64
msgstr "<literal>INFINITY</literal> - <literal>INFINITY</literal> = -<literal>INFINITY</literal>"
68
msgid "Deciding Which Nodes a Resource Can Run On"
69
msgstr "Decidere quale nodo può erogare una risorsa"
73
msgid "<indexterm> <primary>Location Constraints</primary> </indexterm> <indexterm> <primary>Resource</primary><secondary>Constraints</secondary><tertiary>Location</tertiary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Location</secondary> </indexterm> <indexterm> <primary>Location</primary> </indexterm> There are two alternative strategies for specifying which nodes a resources can run on. One way is to say that by default they can run anywhere and then create location constraints for nodes that are not allowed. The other option is to have nodes \"opt-in\"… to start with nothing able to run anywhere and selectively enable allowed nodes."
74
msgstr "Esistono due strategie alternative per specificare su quali nodi può funzionare una risorsa. Una via è quella di dire che di default la risorsa può funzionare ovunque e poi create dei vincoli posizionali (location constraints) per i nodi da escludere. L'altra via è quella di avere nodi che vengano avviati come inabili ad erogare risorse ed fare in modo che questi vengano abilitati selettivamente."
83
msgid "Options for Simple Location Constraints"
84
msgstr "Opzioni per semplici vincoli di locazione (location constraints)"
98
msgid "<literal>id</literal>"
103
msgid "A unique name for the constraint <indexterm> <primary>id</primary><secondary>Location Constraints</secondary> </indexterm> <indexterm> <primary>Location Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Location</secondary><tertiary>id</tertiary> </indexterm> <indexterm> <primary>Location</primary><secondary>id</secondary> </indexterm> <indexterm> <primary>id</primary> </indexterm>"
108
msgid "<literal>rsc</literal>"
113
msgid "A resource name <indexterm> <primary>rsc</primary><secondary>Location Constraints</secondary> </indexterm> <indexterm> <primary>Location Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Location</secondary><tertiary>rsc</tertiary> </indexterm> <indexterm> <primary>Location</primary><secondary>rsc</secondary> </indexterm> <indexterm> <primary>rsc</primary> </indexterm>"
118
msgid "<literal>node</literal>"
123
msgid "A node’s name <indexterm> <primary>node</primary><secondary>Location Constraints</secondary> </indexterm> <indexterm> <primary>Location Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Location</secondary><tertiary>node</tertiary> </indexterm> <indexterm> <primary>Location</primary><secondary>node</secondary> </indexterm> <indexterm> <primary>node</primary> </indexterm>"
128
msgid "<literal>score</literal>"
132
#, fuzzy, no-c-format
133
msgid "Positive values indicate the resource should run on this node. Negative values indicate the resource should not run on this node."
134
msgstr "Valori positivi indicano che la risorsa può funzionare su questo nodo. Valori negativi indicano che la risorsa non può funzionare su questo nodo. Valori di +/- <literal>INFINITY</literal> modificano "può" in "deve"."
138
msgid "Values of +/- <literal>INFINITY</literal> change \"should\"/\"should not\" to \"must\"/\"must not\". <indexterm> <primary>score</primary><secondary>Location Constraints</secondary> </indexterm> <indexterm> <primary>Location Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Location</secondary><tertiary>score</tertiary> </indexterm> <indexterm> <primary>Location</primary><secondary>score</secondary> </indexterm> <indexterm> <primary>score</primary> </indexterm>"
142
#, fuzzy, no-c-format
143
msgid "Asymmetrical \"Opt-In\" Clusters"
144
msgstr "Cluster "Opt-In" asimmetrici"
148
msgid "<indexterm> <primary>Asymmetrical Opt-In Clusters</primary> </indexterm> <indexterm> <primary>Cluster Type</primary><secondary>Asymmetrical Opt-In</secondary> </indexterm> <indexterm> <primary>Asymmetrical Opt-In</primary> </indexterm>"
153
msgid "To create an opt-in cluster, start by preventing resources from running anywhere by default:"
156
#. Tag: programlisting
158
msgid "# crm_attribute --attr-name symmetric-cluster --attr-value false"
163
msgid "Then start enabling nodes. The following fragment says that the web server prefers <literal>sles-1</literal>, the database prefers <literal>sles-2</literal> and both can fail over to <literal>sles-3</literal> if their most preferred node fails."
168
msgid "Example set of opt-in location constraints"
171
#. Tag: programlisting
174
"<constraints>\n"
175
" <rsc_location id=\"loc-1\" rsc=\"Webserver\" node=\"sles-1\" score=\"200\"/>\n"
176
" <rsc_location id=\"loc-2\" rsc=\"Webserver\" node=\"sles-3\" score=\"0\"/>\n"
177
" <rsc_location id=\"loc-3\" rsc=\"Database\" node=\"sles-2\" score=\"200\"/>\n"
178
" <rsc_location id=\"loc-4\" rsc=\"Database\" node=\"sles-3\" score=\"0\"/>\n"
179
"</constraints>"
183
#, fuzzy, no-c-format
184
msgid "Symmetrical \"Opt-Out\" Clusters"
185
msgstr "Cluster "Opt-In" asimmetrici"
189
msgid "<indexterm> <primary>Symmetrical Opt-Out Clusters</primary> </indexterm> <indexterm> <primary>Cluster Type</primary><secondary>Symmetrical Opt-Out</secondary> </indexterm> <indexterm> <primary>Symmetrical Opt-Out</primary> </indexterm>"
194
msgid "To create an opt-out cluster, start by allowing resources to run anywhere by default:"
197
#. Tag: programlisting
199
msgid "# crm_attribute --attr-name symmetric-cluster --attr-value true"
204
msgid "Then start disabling nodes. The following fragment is the equivalent of the above opt-in configuration."
209
msgid "Example set of opt-out location constraints"
212
#. Tag: programlisting
215
"<constraints>\n"
216
" <rsc_location id=\"loc-1\" rsc=\"Webserver\" node=\"sles-1\" score=\"200\"/>\n"
217
" <rsc_location id=\"loc-2-dont-run\" rsc=\"Webserver\" node=\"sles-2\" score=\"-INFINITY\"/>\n"
218
" <rsc_location id=\"loc-3-dont-run\" rsc=\"Database\" node=\"sles-1\" score=\"-INFINITY\"/>\n"
219
" <rsc_location id=\"loc-4\" rsc=\"Database\" node=\"sles-2\" score=\"200\"/>\n"
220
"</constraints>"
225
msgid "Whether you should choose opt-in or opt-out depends both on your personal preference and the make-up of your cluster. If most of your resources can run on most of the nodes, then an opt-out arrangement is likely to result in a simpler configuration. On the other-hand, if most resources can only run on a small subset of nodes an opt-in configuration might be simpler."
230
msgid "What if Two Nodes Have the Same Score"
235
msgid "If two nodes have the same score, then the cluster will choose one. This choice may seem random and may not be what was intended, however the cluster was not given enough information to know any better."
240
msgid "Example of two resources that prefer two nodes equally"
243
#. Tag: programlisting
246
"<constraints>\n"
247
" <rsc_location id=\"loc-1\" rsc=\"Webserver\" node=\"sles-1\" score=\"INFINITY\"/>\n"
248
" <rsc_location id=\"loc-2\" rsc=\"Webserver\" node=\"sles-2\" score=\"INFINITY\"/>\n"
249
" <rsc_location id=\"loc-3\" rsc=\"Database\" node=\"sles-1\" score=\"500\"/>\n"
250
" <rsc_location id=\"loc-4\" rsc=\"Database\" node=\"sles-2\" score=\"300\"/>\n"
251
" <rsc_location id=\"loc-5\" rsc=\"Database\" node=\"sles-2\" score=\"200\"/>\n"
252
"</constraints>"
257
msgid "In the example above, assuming no other constraints and an inactive cluster, Webserver would probably be placed on sles-1 and Database on sles-2. It would likely have placed Webserver based on the node’s uname and Database based on the desire to spread the resource load evenly across the cluster. However other factors can also be involved in more complex configurations."
262
msgid "Specifying in which Order Resources Should Start/Stop"
267
msgid "<indexterm> <primary>Resource</primary><secondary>Constraints</secondary><tertiary>Ordering</tertiary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Ordering</secondary> </indexterm> <indexterm> <primary>Ordering</primary> </indexterm> <indexterm> <primary>Resource</primary><secondary>Start Order</secondary> </indexterm> <indexterm> <primary>Start Order</primary> </indexterm> <indexterm> <primary>Ordering Constraints</primary> </indexterm> The way to specify the order in which resources should start is by creating <literal>rsc_order</literal> constraints."
272
msgid "Properties of an Ordering Constraint"
277
msgid "A unique name for the constraint <indexterm> <primary>id</primary><secondary>Ordering Constraints</secondary> </indexterm> <indexterm> <primary>Ordering Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Ordering</secondary><tertiary>id</tertiary> </indexterm> <indexterm> <primary>Ordering</primary><secondary>id</secondary> </indexterm> <indexterm> <primary>id</primary> </indexterm>"
282
msgid "<literal>first</literal>"
287
msgid "The name of a resource that must be started before the <literal>then</literal> resource is allowed to. <indexterm> <primary>first</primary><secondary>Ordering Constraints</secondary> </indexterm> <indexterm> <primary>Ordering Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Ordering</secondary><tertiary>first</tertiary> </indexterm> <indexterm> <primary>Ordering</primary><secondary>first</secondary> </indexterm> <indexterm> <primary>first</primary> </indexterm>"
292
msgid "<literal>then</literal>"
297
msgid "The name of a resource. This resource will start after the <literal>first</literal> resource. <indexterm> <primary>then</primary><secondary>Ordering Constraints</secondary> </indexterm> <indexterm> <primary>Ordering Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Ordering</secondary><tertiary>then</tertiary> </indexterm> <indexterm> <primary>Ordering</primary><secondary>then</secondary> </indexterm> <indexterm> <primary>then</primary> </indexterm>"
302
msgid "<literal>kind</literal>"
307
msgid "How to enforce the constraint. (<emphasis>Since 1.1.2</emphasis>)"
312
msgid "* Optional - Just a suggestion. Only applies if both resources are starting/stopping."
317
msgid "* Mandatory - Always. If <emphasis>first</emphasis> is stopping or cannot be started, <emphasis>then</emphasis> must be stopped."
322
msgid "* Serialize - Ensure that no two stop/start actions occur concurrently for a set of resources."
327
msgid "<indexterm> <primary>kind</primary><secondary>Ordering Constraints</secondary> </indexterm> <indexterm> <primary>Ordering Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Ordering</secondary><tertiary>kind</tertiary> </indexterm> <indexterm> <primary>Ordering</primary><secondary>kind</secondary> </indexterm> <indexterm> <primary>kind</primary> </indexterm>"
332
msgid "<literal>symmetrical</literal>"
337
msgid "If true, which is the default, stop the resources in the reverse order. Default value: <emphasis>true</emphasis> <indexterm> <primary>symmetrical</primary><secondary>Ordering Constraints</secondary> </indexterm> <indexterm> <primary>Ordering Constraints</primary> </indexterm> <indexterm> <primary>Ordering Constraints</primary><secondary>symmetrical</secondary> </indexterm> <indexterm> <primary>symmetrical</primary> </indexterm>"
342
msgid "Mandatory Ordering"
347
msgid "When the <literal>then</literal> resource cannot run without the <literal>first</literal> resource being active, one should use mandatory constraints. To specify a constraint is mandatory, use scores greater than zero. This will ensure that the then resource will react when the first resource changes state."
352
msgid "If the <literal>first</literal> resource was running and is stopped, the <literal>then</literal> resource will also be stopped (if it is running)."
357
msgid "If the <literal>first</literal> resource was not running and cannot be started, the <literal>then</literal> resource will be stopped (if it is running)."
362
msgid "If the <literal>first</literal> resource is (re)started while the <literal>then</literal> resource is running, the <literal>then</literal> resource will be stopped and restarted."
367
msgid "Advisory Ordering"
372
msgid "On the other hand, when <literal>score=\"0\"</literal> is specified for a constraint, the constraint is considered optional and only has an effect when both resources are stopping and/or starting. Any change in state by the <literal>first</literal> resource will have no effect on the <literal>then</literal> resource."
377
msgid "Example of an optional and mandatory ordering constraint"
380
#. Tag: programlisting
383
"<constraints>\n"
384
" <rsc_order id=\"order-1\" first=\"Database\" then=\"Webserver\" />\n"
385
" <rsc_order id=\"order-2\" first=\"IP\" then=\"Webserver\" score=\"0\"/>\n"
386
"</constraints>"
391
msgid "Some additional information on ordering constraints can be found in the document <ulink url=\"http://www.clusterlabs.org/mediawiki/images/d/d6/Ordering_Explained.pdf\">Ordering Explained</ulink>."
396
msgid "Placing Resources Relative to other Resources"
401
msgid "<indexterm> <primary>Resource</primary><secondary>Constraints</secondary><tertiary>Colocation</tertiary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Colocation</secondary> </indexterm> <indexterm> <primary>Colocation</primary> </indexterm> <indexterm> <primary>Resource</primary><secondary>Location Relative to other Resources</secondary> </indexterm> <indexterm> <primary>Location Relative to other Resources</primary> </indexterm> When the location of one resource depends on the location of another one, we call this colocation."
406
msgid "There is an important side-effect of creating a colocation constraint between two resources: it affects the order in which resources are assigned to a node. If you think about it, it’s somewhat obvious. You can’t place A relative to B unless you know where B is. <footnote><para> While the human brain is sophisticated enough to read the constraint in any order and choose the correct one depending on the situation, the cluster is not quite so smart. Yet. </para></footnote>"
411
msgid "So when you are creating colocation constraints, it is important to consider whether you should colocate A with B or B with A."
416
msgid "Another thing to keep in mind is that, assuming A is collocated with B, the cluster will also take into account A’s preferences when deciding which node to choose for B."
421
msgid "For a detailed look at exactly how this occurs, see the <ulink url=\"http://www.clusterlabs.org/mediawiki/images/6/61/Colocation_Explained.pdf\">Colocation Explained</ulink> document."
426
msgid "Properties of a Collocation Constraint"
431
msgid "A unique name for the constraint. <indexterm> <primary>id</primary><secondary>Colocation Constraints</secondary> </indexterm> <indexterm> <primary>Colocation Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Colocation</secondary><tertiary>id</tertiary> </indexterm> <indexterm> <primary>Colocation</primary><secondary>id</secondary> </indexterm> <indexterm> <primary>id</primary> </indexterm>"
436
msgid "The colocation source. If the constraint cannot be satisfied, the cluster may decide not to allow the resource to run at all. <indexterm> <primary>rsc</primary><secondary>Colocation Constraints</secondary> </indexterm> <indexterm> <primary>Colocation Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Colocation</secondary><tertiary>rsc</tertiary> </indexterm> <indexterm> <primary>Colocation</primary><secondary>rsc</secondary> </indexterm> <indexterm> <primary>rsc</primary> </indexterm>"
441
msgid "<literal>with-rsc</literal>"
446
msgid "The colocation target. The cluster will decide where to put this resource first and then decide where to put the resource in the <literal>rsc</literal> field. <indexterm> <primary>with-rsc</primary><secondary>Colocation Constraints</secondary> </indexterm> <indexterm> <primary>Colocation Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Colocation</secondary><tertiary>with-rsc</tertiary> </indexterm> <indexterm> <primary>Colocation</primary><secondary>with-rsc</secondary> </indexterm> <indexterm> <primary>with-rsc</primary> </indexterm>"
451
msgid "Positive values indicate the resource should run on the same node. Negative values indicate the resources should not run on the same node. Values of +/- <literal>INFINITY</literal> change \"should\" to \"must\". <indexterm> <primary>score</primary><secondary>Colocation Constraints</secondary> </indexterm> <indexterm> <primary>Colocation Constraints</primary> </indexterm> <indexterm> <primary>Constraints</primary><secondary>Colocation</secondary><tertiary>score</tertiary> </indexterm> <indexterm> <primary>Colocation</primary><secondary>score</secondary> </indexterm> <indexterm> <primary>score</primary> </indexterm>"
456
msgid "Mandatory Placement"
461
msgid "Mandatory placement occurs any time the constraint’s score is <literal>+INFINITY</literal> or <literal>-INFINITY</literal>. In such cases, if the constraint can’t be satisfied, then the <literal>rsc</literal> resource is not permitted to run. For <literal>score=INFINITY</literal>, this includes cases where the <literal>with-rsc</literal> resource is not active."
466
msgid "If you need <literal>resource1</literal> to always run on the same machine as <literal>resource2</literal>, you would add the following constraint:"
471
msgid "An example colocation constraint"
474
#. Tag: programlisting
476
msgid "<rsc_colocation id=\"colocate\" rsc=\"resource1\" with-rsc=\"resource2\" score=\"INFINITY\"/>"
481
msgid "Remember, because <literal>INFINITY</literal> was used, if <literal>resource2</literal> can’t run on any of the cluster nodes (for whatever reason) then <literal>resource1</literal> will not be allowed to run."
486
msgid "Alternatively, you may want the opposite… that <literal>resource1</literal> cannot run on the same machine as <literal>resource2</literal>. In this case use <literal>score=\"-INFINITY\"</literal>"
491
msgid "An example anti-colocation constraint"
494
#. Tag: programlisting
496
msgid "<rsc_colocation id=\"anti-colocate\" rsc=\"resource1\" with-rsc=\"resource2\" score=\"-INFINITY\"/>"
501
msgid "Again, by specifying <literal>-INFINTY</literal>, the constraint is binding. So if the only place left to run is where <literal>resource2</literal> already is, then <literal>resource1</literal> may not run anywhere."
506
msgid "Advisory Placement"
511
msgid "If mandatory placement is about \"must\" and \"must not\", then advisory placement is the \"I’d prefer if\" alternative. For constraints with scores greater than <literal>-INFINITY</literal> and less than <literal>INFINITY</literal>, the cluster will try and accommodate your wishes but may ignore them if the alternative is to stop some of the cluster resources."
516
msgid "Like in life, where if enough people prefer something it effectively becomes mandatory, advisory colocation constraints can combine with other elements of the configuration to behave as if they were mandatory."
521
msgid "An example advisory-only colocation constraint"
524
#. Tag: programlisting
526
msgid "<rsc_colocation id=\"colocate-maybe\" rsc=\"resource1\" with-rsc=\"resource2\" score=\"500\"/>"
531
msgid "Ordering Sets of Resources"
536
msgid "A common situation is for an administrator to create a chain of ordered resources, such as:"
541
msgid "A chain of ordered resources"
544
#. Tag: programlisting
547
"<constraints>\n"
548
" <rsc_order id=\"order-1\" first=\"A\" then=\"B\" />\n"
549
" <rsc_order id=\"order-2\" first=\"B\" then=\"C\" />\n"
550
" <rsc_order id=\"order-3\" first=\"C\" then=\"D\" />\n"
551
"</constraints>"
561
msgid "Visual representation of the four resources' start order for the above constraints"
571
msgid "To simplify this situation, there is an alternate format for ordering constraints:"
576
msgid "A chain of ordered resources expressed as a set"
579
#. Tag: programlisting
582
"<constraints>\n"
583
" <rsc_order id=\"order-1\">\n"
584
" <resource_set id=\"ordered-set-example\" sequential=\"true\">\n"
585
" <resource_ref id=\"A\"/>\n"
586
" <resource_ref id=\"B\"/>\n"
587
" <resource_ref id=\"C\"/>\n"
588
" <resource_ref id=\"D\"/>\n"
589
" </resource_set>\n"
590
" </rsc_order>\n"
591
"</constraints>"
596
msgid "Resource sets have the same ordering semantics as groups."
601
msgid "A group resource with the equivalent ordering rules"
604
#. Tag: programlisting
607
"<group id=\"dummy\">\n"
608
" <primitive id=\"A\" .../>\n"
609
" <primitive id=\"B\" .../>\n"
610
" <primitive id=\"C\" .../>\n"
611
" <primitive id=\"D\" .../>\n"
617
msgid "While the set-based format is not less verbose, it is significantly easier to get right and maintain. It can also be expanded to allow ordered sets of (un)ordered resources. In the example below, <literal>rscA</literal> and <literal>rscB</literal> can both start in parallel, as can <literal>rscC</literal> and <literal>rscD</literal>, however <literal>rscC</literal> and <literal>rscD</literal> can only start once <emphasis>both</emphasis> <literal>rscA</literal> <emphasis>and</emphasis> <literal>rscB</literal> are active."
622
msgid "Ordered sets of unordered resources"
625
#. Tag: programlisting
628
"<constraints>\n"
629
" <rsc_order id=\"order-1\">\n"
630
" <resource_set id=\"ordered-set-1\" sequential=\"false\">\n"
631
" <resource_ref id=\"A\"/>\n"
632
" <resource_ref id=\"B\"/>\n"
633
" </resource_set>\n"
634
" <resource_set id=\"ordered-set-2\" sequential=\"false\">\n"
635
" <resource_ref id=\"C\"/>\n"
636
" <resource_ref id=\"D\"/>\n"
637
" </resource_set>\n"
638
" </rsc_order>\n"
639
" </constraints>"
644
msgid "Two Sets of Unordered Resources"
649
msgid "Visual representation of the start order for two ordered sets of unordered resources"
654
msgid "Two ordered sets"
659
msgid "Of course either set — or both sets — of resources can also be internally ordered (by setting <literal>sequential=\"true\"</literal>) and there is no limit to the number of sets that can be specified."
664
msgid "Advanced use of set ordering - Three ordered sets, two of which are internally unordered"
667
#. Tag: programlisting
670
"<constraints>\n"
671
" <rsc_order id=\"order-1\">\n"
672
" <resource_set id=\"ordered-set-1\" sequential=\"false\">\n"
673
" <resource_ref id=\"A\"/>\n"
674
" <resource_ref id=\"B\"/>\n"
675
" </resource_set>\n"
676
" <resource_set id=\"ordered-set-2\" sequential=\"true\">\n"
677
" <resource_ref id=\"C\"/>\n"
678
" <resource_ref id=\"D\"/>\n"
679
" </resource_set>\n"
680
" <resource_set id=\"ordered-set-3\" sequential=\"false\">\n"
681
" <resource_ref id=\"E\"/>\n"
682
" <resource_ref id=\"F\"/>\n"
683
" </resource_set>\n"
684
" </rsc_order>\n"
685
"</constraints>"
690
msgid "Three Resources Sets"
695
msgid "Visual representation of the start order for the three sets defined above"
700
msgid "Three ordered sets"
705
msgid "Collocating Sets of Resources"
710
msgid "Another common situation is for an administrator to create a set of collocated resources. Previously this was possible either by defining a resource group (See <xref linkend=\"group-resources\" />) which could not always accurately express the design; or by defining each relationship as an individual constraint, causing a constraint explosion as the number of resources and combinations grew."
715
msgid "A chain of collocated resources"
718
#. Tag: programlisting
721
"<constraints>\n"
722
" <rsc_colocation id=\"coloc-1\" rsc=\"B\" with-rsc=\"A\" score=\"INFINITY\"/>\n"
723
" <rsc_colocation id=\"coloc-2\" rsc=\"C\" with-rsc=\"B\" score=\"INFINITY\"/>\n"
724
" <rsc_colocation id=\"coloc-3\" rsc=\"D\" with-rsc=\"C\" score=\"INFINITY\"/>\n"
725
"</constraints>"
730
msgid "To make things easier, we allow an alternate form of colocation constraints using <literal>resource_sets</literal>. Just like the expanded version, a resource that can’t be active also prevents any resource that must be collocated with it from being active. For example, if <literal>B was</literal> not able to run, then both <literal>C (+and by inference +D)</literal> must also remain stopped."
735
msgid "The equivalent colocation chain expressed using <literal>resource_sets</literal>"
738
#. Tag: programlisting
741
"<constraints>\n"
742
" <rsc_colocation id=\"coloc-1\" score=\"INFINITY\" >\n"
743
" <resource_set id=\"collocated-set-example\" sequential=\"true\">\n"
744
" <resource_ref id=\"A\"/>\n"
745
" <resource_ref id=\"B\"/>\n"
746
" <resource_ref id=\"C\"/>\n"
747
" <resource_ref id=\"D\"/>\n"
748
" </resource_set>\n"
749
" </rsc_colocation>\n"
750
"</constraints>"
755
msgid "Resource sets have the same colocation semantics as groups."
760
msgid "A group resource with the equivalent colocation rules"
765
msgid "This notation can also be used in this context to tell the cluster that a set of resources must all be located with a common peer, but have no dependencies on each other. In this scenario, unlike the previous, <literal>B would</literal> be allowed to remain active even if <literal>A or</literal> <literal>C</literal> (or both) were inactive."
770
msgid "Using colocation sets to specify a common peer."
773
#. Tag: programlisting
776
"<constraints>\n"
777
" <rsc_colocation id=\"coloc-1\" score=\"INFINITY\" >\n"
778
" <resource_set id=\"collocated-set-1\" sequential=\"false\">\n"
779
" <resource_ref id=\"A\"/>\n"
780
" <resource_ref id=\"B\"/>\n"
781
" <resource_ref id=\"C\"/>\n"
782
" </resource_set>\n"
783
" <resource_set id=\"collocated-set-2\" sequential=\"true\">\n"
784
" <resource_ref id=\"D\"/>\n"
785
" </resource_set>\n"
786
" </rsc_colocation>\n"
787
"</constraints>"
792
msgid "Of course there is no limit to the number and size of the sets used. The only thing that matters is that in order for any member of set N to be active, all the members of set N+1 must also be active (and naturally on the same node); and if a set has <literal>sequential=\"true\"</literal>, then in order for member M to be active, member M+1 must also be active. You can even specify the role in which the members of a set must be in using the set’s role attribute."
797
msgid "A colocation chain where the members of the middle set have no inter-dependencies and the last has master status."
800
#. Tag: programlisting
803
"<constraints>\n"
804
" <rsc_colocation id=\"coloc-1\" score=\"INFINITY\" >\n"
805
" <resource_set id=\"collocated-set-1\" sequential=\"true\">\n"
806
" <resource_ref id=\"A\"/>\n"
807
" <resource_ref id=\"B\"/>\n"
808
" </resource_set>\n"
809
" <resource_set id=\"collocated-set-2\" sequential=\"false\">\n"
810
" <resource_ref id=\"C\"/>\n"
811
" <resource_ref id=\"D\"/>\n"
812
" <resource_ref id=\"E\"/>\n"
813
" </resource_set>\n"
814
" <resource_set id=\"collocated-set-2\" sequential=\"true\" role=\"Master\">\n"
815
" <resource_ref id=\"F\"/>\n"
816
" <resource_ref id=\"G\"/>\n"
817
" </resource_set>\n"
818
" </rsc_colocation>\n"
819
"</constraints>"
824
msgid "Another Three Resources Sets"
829
msgid "Visual representation of a colocation chain where the members of the middle set have no inter-dependencies"
834
msgid "Colocation chain"
840
#~ msgid "A unique name for the constraint"
841
#~ msgstr "Nome univoco per il vincolo (constraint)"
846
#~ msgid "A resource name"
847
#~ msgstr "Nome della risorsa"
852
#~ msgid "A node's uname"
853
#~ msgstr "uname del nodo"
856
#~ msgstr "punteggio"
added
removed
doc/Pacemaker_Explained/it-IT/Ch-Constraints.po
