Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Wed, Dec 29, 2010 at 3:28 PM, Dan Barker <dbarker at visioncomm.net> wrote: >> From: drbd-user-bounces at lists.linbit. >> Sent: Wednesday, December 29, 2010 4:49 PM >> >> I really think drbd is being brain-dead here. Concurrent writes to >> the same LBA aren't an issue... just do it! Note the below is using a >> primary/secondary setup on two raw drbd devices; no GFS anywhere. > > <snip> > > But the result is undefined! What should DRBD write to the other member? The > result of the first or the second write? > > You are using a tool that permits the execution of stupid I/O streams. Good > for stress testing, but not good for data integrity. If you want undefined > data on a DRBD pair, then disconnect before the I/O, do the undefined thing, > and upon reconnect DRBD will faithfully replicate the garbage. It will still > be undefined stuff, but it will be identical undefined stuff. > Are you seriously thinking that Unix doesn't allow two writes to the same LBA simultaneously? This is part of Unix file system semantics. A dead system is not the proper outcome. Chris