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Date: Wed, 06 Dec 2006 17:22:43 +0000
From: Cristian Zamfir <zamf@dcs.gla.ac.uk>
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Subject: [Drbd-dev] lock for reading device state
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Hi,

I am using drbd to implement xen block device migration.  Right now I am 
parsing /proc/drbd to find out if the drives are synchronized and I can 
migrate them. Is there a way to obtain a lock while reading and 
processing this information and prevent other writes to the primary 
device? I need to be able to prevent writes while reading the state of 
the device from a script external to drbd.

In case there is no existing solution, can you please give me a few tips 
on how to start developing such a locking mechanism?

Thank you very much.


Cristian