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<DIV><FONT size=2 face=Verdana><SPAN class=543231317-31032011>Greetings! We have
a few Corosync+PaceMaker+DRBD clusters and a couple older Heartbeat+DRBD
clusters. <SPAN class=543231317-31032011>Our infrastructure is currently located
in a single facility. We have the opportunity to establish a DR site in another
data center over a high bandwidth connection (2-4Gbps). I am thinking of moving
the standby cluster nodes to the secondary data center. One thing that concerns
me is the greater possibility of split-brain scenarios. Currently our clusters
communicate heartbeat through multiple paths: 1. The primary LAN link that users
communicate through; 2. The DRBD link; 3. A dedicated cluster communication LAN.
If we move the standby cluster nodes to the secondary facility, there will no
longer be redundancy on the heartbeat links. Everything will go through the
inter-data-center connection. This concept is a little worrisome. Should I be
very concerned? Is there a way to minimize the risk of split-brain over
WAN?</SPAN></SPAN></FONT></DIV>
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<DIV><SPAN style="FONT-FAMILY: Tahoma; FONT-SIZE: 10pt"><FONT face=Verdana><SPAN
class=543231317-31032011></SPAN></FONT></SPAN> </DIV></FONT></DIV><BR><BR><FONT color=silver><SPAN style="FONT-SIZE: 7.5pt; COLOR: gray; FONT-FAMILY: Verdana"><FONT size=1>Disclaimer - March 31, 2011</FONT></FONT></SPAN></FONT> <P></P><FONT size=1><FONT face=Verdana color=gray><SPAN style="FONT-SIZE: 7.5pt; COLOR: gray; FONT-FAMILY: Verdana">This email and any files <FONT size=1>transmitted</FONT> with it are confidential and intended solely for <STRONG>drbd-user@lists.linbit.com</STRONG></SPAN></FONT><FONT face=Verdana color=gray><SPAN style="FONT-SIZE: 7.5pt; COLOR: gray; FONT-FAMILY: Verdana">. If you are not the named addressee you should not disseminate, distribute, copy or alter this email. Any views or opinions presented in this email are solely those of the author and might not represent those of Physicians' Managed Care or Physician Select Management. Warning: Although Physicians' Managed Care or Physician Select Management has taken reasonable precautions to ensure no viruses are present in this email, the company cannot accept responsibility for any loss or damage arising from the use of this email or attachments.</SPAN></FONT></FONT></BODY></HTML>