Your Losing data because at level quorm with 2 nodes becomes all. Cassandra will not even try to write data after the node goes down . Client should see unavailableexception. For a small window after the failure you will see timedoutexception and those writes should hit the commitlog.
On Wednesday, June 1, 2011, leon hong <codebloc...@gmail.com> wrote: > wait "geili" reply > > 2011/6/1 Preston Chang <zhangyf2...@gmail.com> > > I disable the disk cache of RAID controller, unfortunately it still lost > some data. > > 2011/6/1 Peter Schuller <peter.schul...@infidyne.com> > > > >> 1). set commitlog sync in batch mode and the sync batch window in 0 ms >> 2). one client wrote random keys in infinite loop with consistency level >> QUORUM and record the keys in file after the insert() method return normally >> 3). unplug one server (node A) power cord >> 4). restart the server and cassandra service >> 5). read the key list generated in step 2) with consistency level ONE > > How sure are you that the system is honoring fsync() properly, > including flushing any caches on underlying drives? Or is this with > battery backed caching RAID controllers? > > -- > / Peter Schuller > > > -- > by Preston Chang > > > >
