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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>All,<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am working on a strategy to upgrade my real time highly
available application that uses a drbd resource as its file system for its database.
I am using drbd 8.2.5 and heartbeat 2.1.3, on a CentOS 5.2 server pair. The
idea goes something like this:<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<ol style='margin-top:0in' start=1 type=1>
 <li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
     style='font-size:10.0pt;font-family:Arial'>Set drbd on the Primary host to
     StandAlone, so that the real time app continues to run, but releasing the
     drbd resource on the Secondary host<o:p></o:p></span></font></li>
 <li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
     style='font-size:10.0pt;font-family:Arial'>Mount the drbd resource on the
     secondary, delete the database<o:p></o:p></span></font></li>
 <li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
     style='font-size:10.0pt;font-family:Arial'>Upgrade the real time app and
     its database on the Secondary host<o:p></o:p></span></font></li>
 <li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
     style='font-size:10.0pt;font-family:Arial'>Switch the running real time
     app to the Secondary host<o:p></o:p></span></font></li>
 <li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
     style='font-size:10.0pt;font-family:Arial'>Reconnect the drbd resource on
     the Primary host to the Secondary host, and resync from Secondary to
     Primary<o:p></o:p></span></font></li>
</ol>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I&#8217;ve gone over the drbdadm tool, and I think the steps
are something like:<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>(on Primary) </span></font><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>drbdadm disconnect pgsql</span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>(on Secondary) drbdadm </span></font><font size=2
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>primary
pgsql; mount /dev/drbd0 /mirror</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Upgrade app and db on Secondary<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Switch running app to Secondary<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>(on Secondary) </span></font><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>drbdadm invalidate-remote
pgsql</span></font><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>(on Primary) </span></font><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>drbdadm connect pgsql</span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Can someone confirm that I&#8217;ve got the right commands
and in the right order? Have I provided enough info? Its one of those things
where I know I could probably hose the servers if I don&#8217;t do it right,
and I&#8217;ve pretty much got one shot to get it right.<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks for your help,<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Doug Knight<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>WSI Corp<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

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