<font size=2 face="sans-serif">Hello,</font>
<br>
<br><font size=2 face="sans-serif">I've installed ....</font>
<br>
<br><font size=2 face="sans-serif"># yum info glusterfs-server</font>
<br><font size=2 face="sans-serif">Loaded plugins: fastestmirror</font>
<br><font size=2 face="sans-serif">Loading mirror speeds from cached hostfile</font>
<br><font size=2 face="sans-serif">Installed Packages</font>
<br><font size=2 face="sans-serif">Name : glusterfs-server</font>
<br><font size=2 face="sans-serif">Arch : x86_64</font>
<br><font size=2 face="sans-serif">Version : 3.7.6</font>
<br><font size=2 face="sans-serif">Release : 1.el7</font>
<br><font size=2 face="sans-serif">Size : 4.3
M</font>
<br><font size=2 face="sans-serif">Repo : installed</font>
<br><font size=2 face="sans-serif">From repo : latest</font>
<br><font size=2 face="sans-serif">Summary : Clustered file-system
server</font>
<br><font size=2 face="sans-serif">URL : </font><a href=http://www.gluster.org/docs/index.php/GlusterFS><font size=2 color=blue face="sans-serif">http://www.gluster.org/docs/index.php/GlusterFS</font></a>
<br><font size=2 face="sans-serif">License : GPLv2 or LGPLv3+</font>
<br><font size=2 face="sans-serif">Description : GlusterFS is a distributed
file-system capable of scaling to several</font>
<br><font size=2 face="sans-serif">
: petabytes. It aggregates various storage bricks over Infiniband RDMA</font>
<br><font size=2 face="sans-serif">
: or TCP/IP interconnect into one large parallel network file</font>
<br><font size=2 face="sans-serif">
: system. GlusterFS is one of the most sophisticated file systems in</font>
<br><font size=2 face="sans-serif">
: terms of features and extensibility. It borrows a powerful concept</font>
<br><font size=2 face="sans-serif">
: called Translators from GNU Hurd kernel. Much of the code in GlusterFS</font>
<br><font size=2 face="sans-serif">
: is in user space and easily manageable.</font>
<br><font size=2 face="sans-serif">
:</font>
<br><font size=2 face="sans-serif">
: This package provides the glusterfs server daemon.</font>
<br>
<br><font size=2 face="sans-serif">I wanted to build a ...</font>
<br>
<br><font size=2 face="sans-serif"># gluster volume create gv0 replica
3 arbiter 1 d90029:/data/brick0 d90031:/data/brick0 d90034:/data/brick0</font>
<br><font size=2 face="sans-serif">volume create: gv0: success: please
start the volume to access data</font>
<br>
<br><font size=2 face="sans-serif">... but I got a ...</font>
<br>
<br><font size=2 face="sans-serif"># gluster volume info</font>
<br>
<br><font size=2 face="sans-serif">Volume Name: gv0</font>
<br><font size=2 face="sans-serif">Type: Replicate</font>
<br><font size=2 face="sans-serif">Volume ID: 329325fc-ceed-4dee-926f-038f44281678</font>
<br><font size=2 face="sans-serif">Status: Created</font>
<br><font size=2 face="sans-serif">Number of Bricks: </font><font size=2 color=#ff4040 face="sans-serif"><b>1
x 3 = 3</b></font>
<br><font size=2 face="sans-serif">Transport-type: tcp</font>
<br><font size=2 face="sans-serif">Bricks:</font>
<br><font size=2 face="sans-serif">Brick1: d90029:/data/brick0</font>
<br><font size=2 face="sans-serif">Brick2: d90031:/data/brick0</font>
<br><font size=2 face="sans-serif">Brick3: d90034:/data/brick0</font>
<br><font size=2 face="sans-serif">Options Reconfigured:</font>
<br><font size=2 face="sans-serif">performance.readdir-ahead: on</font>
<br>
<br><font size=2 face="sans-serif">... without the requested arbiter !</font>
<br>
<br><font size=2 face="sans-serif">The same situation with 6 bricks ...</font>
<br>
<br><font size=2 face="sans-serif"># gluster volume create gv0 replica
3 arbiter 1 d90029:/data/brick0 d90031:/data/brick0 d90034:/data/brick0
d90029:/data/brick1 d90031:/data/brick1 d90034:/data/brick1</font>
<br><font size=2 face="sans-serif">volume create: gv0: success: please
start the volume to access data</font>
<br><font size=2 face="sans-serif">[root@d90029 ~]# gluster vol info</font>
<br>
<br><font size=2 face="sans-serif">Volume Name: gv0</font>
<br><font size=2 face="sans-serif">Type: Distributed-Replicate</font>
<br><font size=2 face="sans-serif">Volume ID: 2b8dbcc0-c4bb-41e3-a870-e164d8d10c49</font>
<br><font size=2 face="sans-serif">Status: Created</font>
<br><font size=2 face="sans-serif">Number of Bricks: </font><font size=2 color=#ff4040 face="sans-serif"><b>2
x 3 = 6</b></font>
<br><font size=2 face="sans-serif">Transport-type: tcp</font>
<br><font size=2 face="sans-serif">Bricks:</font>
<br><font size=2 face="sans-serif">Brick1: d90029:/data/brick0</font>
<br><font size=2 face="sans-serif">Brick2: d90031:/data/brick0</font>
<br><font size=2 face="sans-serif">Brick3: d90034:/data/brick0</font>
<br><font size=2 face="sans-serif">Brick4: d90029:/data/brick1</font>
<br><font size=2 face="sans-serif">Brick5: d90031:/data/brick1</font>
<br><font size=2 face="sans-serif">Brick6: d90034:/data/brick1</font>
<br><font size=2 face="sans-serif">Options Reconfigured:</font>
<br><font size=2 face="sans-serif">performance.readdir-ahead: on</font>
<br>
<br>
<br><font size=2 face="sans-serif">In contrast the documentation tells
....</font>
<br>
<br>
<br><font size=2 face="sans-serif"><b>Arbiter configuration</b></font>
<p><font size=2 face="sans-serif">The arbiter configuration a.k.a. the
arbiter volume is the perfect sweet spot between a 2-way replica and 3-way
replica to avoid files getting into split-brain, <b><i>without the 3x storage
space</i></b> as mentioned earlier. The syntax for creating the volume
is:</font>
<p><font size=2 face="sans-serif"><b>gluster volume create replica 3 arbiter
1 host1:brick1 host2:brick2 host3:brick3</b></font>
<p><font size=2 face="sans-serif">For example:</font>
<p><font size=2 face="sans-serif"><b>gluster volume create testvol replica
3 arbiter 1 127.0.0.2:/bricks/brick{1..6} force</b></font>
<p><font size=2 face="sans-serif">volume create: testvol: success: please
start the volume to access data</font>
<p><font size=2 face="sans-serif"><b>gluster volume info</b></font>
<p><font size=2 face="sans-serif">Volume Name: testvol<br>
Type: Distributed-Replicate<br>
Volume ID: ae6c4162-38c2-4368-ae5d-6bad141a4119<br>
Status: Created<br>
Number of Bricks: </font><font size=2 color=#ff4040 face="sans-serif"><b>2
x (2 + 1) = 6</b></font><font size=2 face="sans-serif"><br>
Transport-type: tcp<br>
Bricks:<br>
Brick1: 127.0.0.2:/bricks/brick1<br>
Brick2: 127.0.0.2:/bricks/brick2<br>
Brick3: 127.0.0.2:/bricks/brick3 </font><font size=2 color=#ff4040 face="sans-serif"><b>(arbiter)</b></font><font size=2 face="sans-serif"><br>
Brick4: 127.0.0.2:/bricks/brick4<br>
Brick5: 127.0.0.2:/bricks/brick5<br>
Brick6: 127.0.0.2:/bricks/brick6 </font><font size=2 color=#ff4040 face="sans-serif"><b>(arbiter)</b></font><font size=2 face="sans-serif"><br>
Options Reconfigured : transport.address-family: inet<br>
performance.readdir-ahead: on `</font>
<br>
<br>
<br>
<br><font size=2 face="sans-serif">What's going wrong ? Can anybody help
?</font>
<br>
<br><font size=2 face="sans-serif">Kind Regards</font>
<br><font size=2 face="sans-serif">Ralf Simon</font>
<br>
<br>
<br>