I wonder if you can point me to the message or the title of the message. It seems that I cannot find the message ...
Thanks, -JQ On Mon, Nov 30, 2009 at 4:36 PM, Berk D. Demir <[email protected]> wrote: > Short answer is "yes you can still lose data". > It's about HDFS and HDFS-265 will solve this. > Similar question was in the list a couple of days ago. > Here's Ryan's answer. > http://mail-archives.apache.org/mod_mbox/hadoop-hbase-user/200911.mbox/browser > > On Mon, Nov 30, 2009 at 00:18, JQ Hadoop <[email protected]> wrote: >> I have a question regarding the durability of HBase. After I have put >> a record to HBase and have received a confirmation of the put from the >> region server (assuming both autoFlush and writeToWAL are set to >> true), can I be sure that my record will be there no matter what? I've >> checked the code and found that the region server will first append a >> log record to WAL (a SequenceFile) and then may call the sync() >> function; however, it appears to me that this does not guarantee the >> log record is in HDFS even if the sync() function is called. That is >> to say, in case of RegionServer crash, the records put into HBase may >> be lost; am I missing anything? >> >> Thanks, >> -JQ >> >
