Using nfs for a distribited System like Cassandra is like putting a Ferrari on a Truck and going for a Race with the Truck. It is simply nonsense.
Am 01.11.2016 19:39 schrieb "Vladimir Yudovin" <vla...@winguzone.com>: > Hi, > > it's not only performance issue. In case of network problem writer tread > can be blocked, also in case of failure loss of data can occur. > > Best regards, Vladimir Yudovin, > > *Winguzone <https://winguzone.com?from=list> - Hosted Cloud > CassandraLaunch your cluster in minutes.* > > > ---- On Tue, 01 Nov 2016 14:10:10 -0400*John Sanda <john.sa...@gmail.com > <john.sa...@gmail.com>>* wrote ---- > > I know that using NFS is discouraged, particularly for the commit log. Can > anyone shed some light into what kinds of problems I might encounter aside > from performance? The reason for my inquiry is because I have some > deployments with Cassandra 2.2.1 that use NFS and are experiencing some > problems like reoccurring corrupted commit log segments on start up: > > ERROR 19:38:42 Exiting due to error while processing commit log during > initialization. > > org.apache.cassandra.db.commitlog.CommitLogReplayer$CommitLogReplayException: > Mutation checksum failure at 33296351 in CommitLog-5-1474325237114.log > at > org.apache.cassandra.db.commitlog.CommitLogReplayer.handleReplayError(CommitLogReplayer.java:622) > [apache-cassandra-2.2.1.jar] > at > org.apache.cassandra.db.commitlog.CommitLogReplayer.replaySyncSection(CommitLogReplayer.java:492) > [apache-cassandra-2.2.1.jar] > at > org.apache.cassandra.db.commitlog.CommitLogReplayer.recover(CommitLogReplayer.java:388) > [apache-cassandra-2.2.1.jar] > at > org.apache.cassandra.db.commitlog.CommitLogReplayer.recover(CommitLogReplayer.java:147) > [apache-cassandra-2.2.1.jar] > at > org.apache.cassandra.db.commitlog.CommitLog.recover(CommitLog.java:189) > [apache-cassandra-2.2.1.jar] > at > org.apache.cassandra.db.commitlog.CommitLog.recover(CommitLog.java:169) > [apache-cassandra-2.2.1.jar] > at > org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java:266) > [apache-cassandra-2.2.1.jar] > at > org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:488) > [apache-cassandra-2.2.1.jar] > at > org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:595) > [apache-cassandra-2.2.1.jar] > > > In one deployment after removing all of corrupted commit log segments I > got a different error: > > Exception (java.lang.RuntimeException) encountered during startup: > java.nio.file.NoSuchFileException: > /cassandra_data/data/hawkular_metrics/metrics_idx-1ea881506ee311e6890b131c1bc89929/la-86-big-Statistics.db > java.lang.RuntimeException: java.nio.file.NoSuchFileException: > /cassandra_data/data/hawkular_metrics/metrics_idx-1ea881506ee311e6890b131c1bc89929/la-86-big-Statistics.db > at > org.apache.cassandra.io.util.ChannelProxy.openChannel(ChannelProxy.java:55) > at > org.apache.cassandra.io.util.ChannelProxy.<init>(ChannelProxy.java:66) > at > org.apache.cassandra.io.util.RandomAccessReader.open(RandomAccessReader.java:78) > at > org.apache.cassandra.io.sstable.metadata.MetadataSerializer.deserialize(MetadataSerializer.java:91) > at > org.apache.cassandra.io.sstable.metadata.MetadataSerializer.deserialize(MetadataSerializer.java:101) > at > org.apache.cassandra.db.ColumnFamilyStore.removeUnfinishedCompactionLeftovers(ColumnFamilyStore.java:672) > at > org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java:216) > at > org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:488) > at > org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:595) > Caused by: java.nio.file.NoSuchFileException: > /cassandra_data/data/hawkular_metrics/metrics_idx-1ea881506ee311e6890b131c1bc89929/la-86-big-Statistics.db > at > sun.nio.fs.UnixException.translateToIOException(UnixException.java:86) > at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102) > at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107) > at > sun.nio.fs.UnixFileSystemProvider.newFileChannel(UnixFileSystemProvider.java:177) > at java.nio.channels.FileChannel.open(FileChannel.java:287) > at java.nio.channels.FileChannel.open(FileChannel.java:335) > at > org.apache.cassandra.io.util.ChannelProxy.openChannel(ChannelProxy.java:51) > ... 8 more > > > The latter error looks like it involves compaction and might be unrelated. > I don't know if it matters, but I have commit log compression enabled in > these environments. > > -- > > - John > > >
