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, Mar 14, 2007 at 07:28:22AM +0200, Siim Vahtre wrote: > Thank you for your answer! > > >if your hardware pretends to have done something which it actually did > >not do, there is no drbd magic to cover for you. > > I am completely aware of that and I was not hoping for any "magic". I just > thought that maybe thanks do ordered writes and some consistency > flags/counters, But your controller doesn't guarantee that, as it can reorder internally the requests (hey, if it doesn't obey flush requests, why would it obey the order of the requests when finally flushing?). Note that your controller is broken as far as any transactional system is concerned. Postresql, Oracle, etc. *will* believe it when it says it committed some data to persistent storage, so if your controller or power decides to die then, you've just lost a bunch of transactions your system believed commited. In short, there's no ACID. Some controllers that provide write-cache also support an internal battery that provides power long enough to flush the data. Check your manuals or vendor. -- lfr 0/0 -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 189 bytes Desc: not available URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20070314/6249ef0f/attachment.pgp>