Ryan:
actually I really like this decoupling Hbase/filesystem :)
Thanks again all for your replies
Cheers, TR

Ryan Rawson wrote:
Hey,

When you start hbase in a fresh installation it will use local fs in
/tmp.  The hadoop filesystem libraries we use allow the use of at
least 3 filesystems (local, hdfs, kfs).  Right now you are seeing the
single ZK process and the combined HBase master/regionserver process.

HBase needs the following things out of it's filesystem:
- global view - every single regionserver & master MUST see every file
from everyone at all times.  1 hour rsync won't cut it.
- high bandwidth, once you get 3+ servers doing high IO (compaction,
etc), you wont want to rely on a 1 disk NFS.

In theory you can use something like NFS and common mount dir on all
regionservers/masters. This won't scale of course. It should _in
theory_ work... You can specify the rootdir with something like
"file:///nfs_mount_path/hbase".  Normally we'd say
hdfs://namenode:port/hbase

The hbase scripts don't boot up or control hadoop at all. You must
provide a working hadoop, then hbase can use it. It may seem a little
"annoying" to have a 2 step process, but the decoupled control makes
our control scripts more generic and suitable for all.

Good luck out there!
-ryan

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