Mailing List Archive: Memmory mapped files

On Wed, Nov 08, 2000 at 02:23:20PM +0100, Andrej Hosna wrote:
> Hello,
> I 'm using drbd to create virtual raid for two host. On the shared partition I
> use memmory mapped files for some of the application. Sometimes, after changing
> status of nodes PRI->SEC SEC->PRI , I get corrupted memmory mapped files. Have
> some of you people experienced something like this? I want to ask about this
> before I'll investigate this more.

It is not quite clear what you are asking. Please describe the sequence of
events more fully.

But, if you are trying to have the drbd volume mounted on both sides at
the same time, that will not work without coordination from the application,
eg, a cluster filesystem like GFS with a lock manager, or Oracle OPS or
such like. This is because the secondary recieves writes from the primary,
but only writes them straight to disk, without making the buffer cache
consistant with the new disk image.

-dg

--
David Gould dg@example.com
SuSE, Inc., 580 2cd St. #210, Oakland, CA 94607 510.628.3380
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