Striping Across Four Storage Nodes With GlusterFS On Mandriva 2010.0

Author: Falko Timme

This tutorial shows how to do data striping (segmentation of logically sequential data, such as a single file, so that segments can be assigned to multiple physical devices in a round-robin fashion and thus written concurrently) across four single storage servers (running Mandriva 2010.0) with GlusterFS. The client system (Mandriva 2010.0 as well) will be able to access the storage as if it was a local filesystem. GlusterFS is a clustered file-system capable of scaling to several peta-bytes. It aggregates various storage bricks over Infiniband RDMA or TCP/IP interconnect into one large parallel network file system. Storage bricks can be made of any commodity hardware such as x86_64 servers with SATA-II RAID and Infiniband HBA.

Please note that this kind of storage doesn't provide any high-availability/fault tolerance features, as would be the case with replicated storage.

I do not issue any guarantee that this will work for you!

1 Preliminary Note

In this tutorial I use five systems, four servers and a client:

server1.example.com: IP address 192.168.0.100 (server)
server2.example.com: IP address 192.168.0.101 (server)
server3.example.com: IP address 192.168.0.102 (server)
server4.example.com: IP address 192.168.0.103 (server)
client1.example.com: IP address 192.168.0.104 (client)

All five systems should be able to resolve the other systems' hostnames. If this cannot be done through DNS, you should edit the /etc/hosts file so that it looks as follows on all five systems:

vi /etc/hosts

127.0.0.1       localhost.localdomain   localhost
192.168.0.100   server1.example.com     server1
192.168.0.101   server2.example.com     server2
192.168.0.102   server3.example.com     server3
192.168.0.103   server4.example.com     server4
192.168.0.104   client1.example.com     client1

(It is also possible to use IP addresses instead of hostnames in the following setup. If you prefer to use IP addresses, you don't have to care about whether the hostnames can be resolved or not.)

2 Setting Up The GlusterFS Servers

server1.example.com/server2.example.com/server3.example.com/server4.example.com:

GlusterFS is available as a package for Mandriva 2010.0, therefore we can install it as follows:

urpmi glusterfs-server

The command

glusterfs --version

should now show the GlusterFS version that you've just installed (2.0.6 in this case):

[root@server1 administrator]# glusterfs --version
glusterfs 2.0.6 built on Sep 20 2009 06:40:50
Repository revision: v2.0.6
Copyright (c) 2006-2009 Z RESEARCH Inc. <http://www.zresearch.com>
GlusterFS comes with ABSOLUTELY NO WARRANTY.
You may redistribute copies of GlusterFS under the terms of the GNU General Public License.
[root@server1 administrator]#

Next we create a few directories:

mkdir /data/
mkdir /data/export
mkdir /data/export-ns

Now we create the GlusterFS server configuration file /etc/glusterfs/glusterfsd.vol which defines which directory will be exported (/data/export) and what client is allowed to connect (192.168.0.104 = client1.example.com):

vi /etc/glusterfs/glusterfsd.vol

volume posix
  type storage/posix
  option directory /data/export
end-volume

volume locks
  type features/locks
  subvolumes posix
end-volume

volume brick
  type performance/io-threads
  option thread-count 8
  subvolumes locks
end-volume

volume server
  type protocol/server
  option transport-type tcp/server
  option auth.addr.brick.allow 192.168.0.104
  subvolumes brick
end-volume

Please note that it is possible to use wildcards for the IP addresses (like 192.168.*) and that you can specify multiple IP addresses separated by comma (e.g. 192.168.0.104,192.168.0.105).

Afterwards we restart the GlusterFS server:

/etc/init.d/glusterfsd restart

Striping Across Four Storage Nodes With GlusterFS On Mandriva 2010.0