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<!--StartFragment--><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">Feri,</div><p style="margin:0in;font-family:Calibri;font-size:11.0pt" class=""> </p><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">I have a follow-up
question:</div><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class=""><br class=""></div><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">We are trying to
achieve an NDU for our Master/Slave resource - this is why the resource
parameter is being updated.</div><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">The desired sequence
of events is as follows:</div>
<ol type="1" style="margin-left: 0.375in; direction: ltr; unicode-bidi: embed; margin-top: 0in; margin-bottom: 0in; font-family: Calibri; font-size: 11pt;" class="">
<li value="1" style="margin-top:0;margin-bottom:0;vertical-align:middle" class=""><span style="font-size: 11pt;" class="">Resource parameter is updated
in pacemaker.</span></li>
<li style="margin-top:0;margin-bottom:0;vertical-align:middle" class=""><span style="font-size: 11pt;" class="">Slave instance is reloaded
(or restarted) to pickup the new parameter. This may take several minutes
with out resource.</span></li>
<li style="margin-top:0;margin-bottom:0;vertical-align:middle" class=""><span style="font-size: 11pt;" class="">Once Slave is back online,
Master is demoted and Slave is promoted.</span></li>
<li style="margin-top:0;margin-bottom:0;vertical-align:middle" class=""><span style="font-size: 11pt;" class="">Former master is reloaded (or
restarted) to pickup the new parameter.</span></li>
</ol><p style="margin:0in;margin-left:.375in;font-family:Calibri;font-size:11.0pt" class=""> </p><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">This seems to me as
a fairly standard sequence for updating any Master/Slave resource - restarting
both instances at the same time is never a good thing.</div><p style="margin:0in;font-family:Calibri;font-size:11.0pt" class=""> </p><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">I can't come up with
a way to create such a sequence.</div><p style="margin:0in;font-family:Calibri;font-size:11.0pt" class=""> </p><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">The best I can come
up with is to implement a reload action in our resource agent, which</div><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class=""> for the slave instance would restart it
immediately, and</div><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class=""> for the master instance would wait a fixed
time (3 min) to give Slave time to reload, and then return OCF_ERR_GENERIC to
force a failover.</div><p style="margin:0in;font-family:Calibri;font-size:11.0pt" class=""> </p><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">This kind of works,
but is quite hacky - there is no guarantee that the Slave will be done
reloading in 3 min, and we also returning error intentionally.</div><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">I thought of using
notify action, but there is no notify about the reload action, so it does not
work.</div><p style="margin:0in;font-family:Calibri;font-size:11.0pt" class=""> </p><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">Any other
suggestions?</div><p style="margin:0in;font-family:Calibri;font-size:11.0pt" class=""> </p><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">Thanks a lot</div><p style="margin:0in;font-family:Calibri;font-size:11.0pt" class=""> </p><div style="margin: 0in; font-family: Calibri; font-size: 11pt;" class="">Ilia</div>
<!--EndFragment--><div><br class=""><blockquote type="cite" class=""><div class="">On Jun 10, 2016, at 3:13 AM, Ferenc Wágner <<a href="mailto:wferi@niif.hu" class="">wferi@niif.hu</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">Ilia Sokolinski <<a href="mailto:ilia@clearskydata.com" class="">ilia@clearskydata.com</a>> writes:<br class=""><br class=""><blockquote type="cite" class="">We have a custom Master-Slave resource running on a 3-node pcs cluster on CentOS 7.1<br class=""><br class="">As part of what is supposed to be an NDU we do update some properties of the resource.<br class="">For some reason this causes both Master and Slave instances of the resource to be restarted.<br class=""><br class="">Since restart takes a fairly long time for us, the update becomes very much disruptive.<br class=""><br class="">Is this expected? <br class=""></blockquote><br class="">Yes, if you changed a parameter declared with unique="1" in your resource<br class="">agent metadata.<br class=""><br class=""><blockquote type="cite" class="">We have not seen this behavior with the previous release of pacemaker.<br class=""></blockquote><br class="">I'm surprised...<br class="">-- <br class="">Feri<br class=""></div></blockquote></div><br class=""></body></html>