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<DIV><FONT face=Arial size=2>Lars:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Is this true with all protocol versions (i.e. A, B,
C)?</FONT></DIV>
<DIV><FONT face=Arial size=2>And is this true on earlier versions of drbd (i.e.
prior to 8.x)?</FONT></DIV>
<DIV>
<P><FONT face="Century Gothic" color=#999999 size=2>Ron Blechman<FONT
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</FONT>Distinguished Member of Technical Staff<FONT face="Times New Roman"
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</FONT>Avaya<FONT face="Century Gothic" color=#000000 size=2> </FONT><FONT
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Road<FONT face="Times New Roman" color=#000000 size=3> </FONT><FONT
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</FONT><FONT face="Century Gothic" color=#ff0033 size=2>|</FONT><BR>Voice
732.852.2310 <FONT color=#ff0033>| </FONT>Fax 732.852.1375<FONT
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=lars.ellenberg@linbit.com
href="mailto:lars.ellenberg@linbit.com">Lars Ellenberg</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=drbd-user@lists.linbit.com
href="mailto:drbd-user@lists.linbit.com">drbd-user@lists.linbit.com</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, November 24, 2007 1:31
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [DRBD-user] Preventing
initial full sync on new install</DIV>
<DIV><BR></DIV><!-- Converted from text/plain format -->
<P><FONT size=2>On Thu, Nov 22, 2007 at 06:00:32PM +0100, Christophe Boyanique
wrote:<BR>><BR>> Hello,<BR>><BR>> I will have to convert a cluster
from external bay sharing to DRBD<BR>> duplication and the main concern of
the client is to reduce the outage<BR>> as services are in
production.<BR>><BR>> The documentation states:<BR>><BR>> You
choose which node shall become Primary for the first time (the one<BR>>
with the good data, if you have some), then you do drbdadm --<BR>>
--overwrite-data-of-peer primary all. The result is a full<BR>>
synchronization of the underlying devices (we call this the initial
full<BR>> sync).<BR>> The device is usable right away, so if you have no
file system already,<BR>> you should create one
now.<BR>><BR>><BR>> My question is; will the device be usable right
away during the initial<BR>> full sync or will it be blocked ?<BR><BR>as
you quoted above, and as Stefan Seifert pointed out,<BR>the device _is_ usable
right away.<BR><BR>> If the device is not accessible; what is the purpose
of this full sync<BR><BR>what is the purpose of the initial sync of a raid1
device?<BR><BR>> as, anyway, the device will be formated right away after
the full sync ?<BR><BR>if you have existing data, you'd not want to format it
away.<BR><BR>> Is there a way to avoid this initial full sync or to reduce
the duration ?<BR><BR>yes.<BR>but you should not.<BR><BR>especially in your
case, what I'd do is:<BR> unplug that external bay from one of the
nodes.<BR> attach some new storage to that node.<BR><BR> configure
drbd with external meta data to use the existing data on the<BR> node
that still sees it, make it primary there, and start
your<BR> services.<BR><BR> then start drbd on the node with the
newly attached storage,<BR> and let it sync up.<BR><BR> now,
understand and configure heartbeat.<BR><BR>--<BR>: commercial DRBD/HA support
and consulting: sales at linbit.com :<BR>: Lars
Ellenberg
Tel +43-1-8178292-0 :<BR>: LINBIT Information Technologies
GmbH Fax +43-1-8178292-82 :<BR>: Vivenotgasse
48, A-1120 Vienna/Europe <A
href="http://www.linbit.com">http://www.linbit.com</A> :<BR>__<BR>please use
the "List-Reply" function of your email
client.<BR>_______________________________________________<BR>drbd-user
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