<br><br><div class="gmail_quote">On Wed, Jan 13, 2010 at 3:25 AM, Miki Shapiro <span dir="ltr"><<a href="mailto:Miki.Shapiro@coles.com.au">Miki.Shapiro@coles.com.au</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
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<div>
<p class="MsoNormal">Hi all</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">I’m attempting to build a 2-way cluster, SLES-11-based
with an openais/pacemaker stack. I’ve got the nodes and a resource (a
drbd volume) happening. What I’m not sure about is the active CRM DC
election process. </p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">I configured a null stonith resource for each node. </p>
<p class="MsoNormal">I have stonith-enabled set to true ( I will implement a real
stonith facility once final solution is in place)</p>
<p class="MsoNormal">I have no-quorum-policy set to ignore (as the cluster is expected
to work with one node active).</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">I look at crm_mon or crm_gui, and it’s all green and
happy.</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">I now go and halt a node. </p></div></div></blockquote><div><br></div><div>define "halt"</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div lang="EN-AU" link="blue" vlink="purple"><div>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Observing crm_mon or crm_gui on node2, I expect to see :</p>
<p><span>1.<span style="font:7.0pt "Times New Roman"">
</span></span>Services appear as down thanks to resource monitoring
directives.</p>
<p><span>2.<span style="font:7.0pt "Times New Roman"">
</span></span>The quorum broken (… do I care?)</p>
<p><span>3.<span style="font:7.0pt "Times New Roman"">
</span></span>The new node elected as DC. Despite what the book
states (here: < <a href="http://www.clusterlabs.org/doc/en-US/Pacemaker/1.0/html/Pacemaker_Explained/s-cluster-status.html" target="_blank">http://www.clusterlabs.org/doc/en-US/Pacemaker/1.0/html/Pacemaker_Explained/s-cluster-status.html</a>
> at the bottom) that:</p>
<p><i>“The DC (Designated Controller) node is
where all the decisions are made and if the current DC fails a new one is
elected from the remaining cluster nodes. The choice of DC is of no
significance to an administrator beyond the fact that its logs will generally
be more interesting.”</i></p>
<p> </p>
<p>Is of significance. I want the brain, in as far as
the surviving node is concerned, to be running on a non-halted server. </p>
<p> </p>
<p class="MsoNormal">What happens in practice is:</p>
<p class="MsoNormal">If I halt the DC, </p>
<p><span>1.<span style="font:7.0pt "Times New Roman"">
</span></span>Resources DO appear stopped and do-their-thing™</p>
<p><span>2.<span style="font:7.0pt "Times New Roman"">
</span></span>[PROBLEM?] Quorum DOES NOT appear as broken</p>
<p><span>3.<span style="font:7.0pt "Times New Roman"">
</span></span>[PROBLEM?] The remaining node DOES NOT get (visibly)
elected as the new DC.</p>
<p class="MsoNormal">If I halted the non-DC node, </p>
<p><span>1.<span style="font:7.0pt "Times New Roman"">
</span></span>Resources DO appear stopped and do-their-thing™</p>
<p><span>2.<span style="font:7.0pt "Times New Roman"">
</span></span>Quorum DOES appear as broken</p>
<p><span>3.<span style="font:7.0pt "Times New Roman"">
</span></span>[PROBLEM?]The remaining node DOES NOT get (visibly)
elected as the new DC.</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Now if my understanding serves me right, the DC is the
baton-holding CRM that does the thinking for the entire cluster. If the
surviving node1 think that the (DEAD) node2 is the de-facto brains of the
cluster and doesn’t take the reigns, I have a dysfunctional cluster.</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Can someone please offer some clarification on how one would
reasonably expect this to work?</p></div></div></blockquote><div><br></div><div>Not without logs (one per scenario as bzip'd attchments please).</div></div>