= GlusterFS Server =

== Network ==

The GlusterFS servers will have fixed IP-addresses. That is configured in the DHCP servers list of statically assigned IP-adresses by using the Domains MAC address.

 * 192.168.1.42 gluster01
 * 192.168.1.43 gluster02
 * 192.168.1.44 gluster03

== Disk ==

=== Add hardware ===
To keep things separated the OS will be on one disk and the glusterfs filesystem will be on another disk. We will [[Domain Editing|add a disk]] to the domain. This disk will be used for the glusterfs file storage.

=== Configure disk ===

==== Partition ====
Create one large partition on `/dev/vdb` with partition type `8e Linux LVM`.

==== LVM ====
Set up a new physical volume, configure a volume group and add a volume
{{{
pvcreate /dev/vdb1
vgcreate vg_data /dev/vdb1
lvcreate --size 4G --name gluster_www vg_data
}}}

==== Format ====
Create a filesystem on the volume.
{{{
mkfs.ext4 /dev/vg_data/gluster_www
}}}

==== Mountpoint ====
Create the mountpoint.
{{{
mkdir /srv/www
}}}

==== fstab ====
Add the volume to `/etc/fstab`.
{{{
/dev/vg_data/gluster_www /srv/www        ext4   defaults        0       0
}}}

==== Mount ====
Mount the new volume.
{{{
mount /srv/www
}}}
If the mount command does not succeed, it it most likely because the fstab entry is incorrect.

== Software ==

=== Mount Point ===
Glusterfs is not happy about using a directory which is also a mountpoint.

''volume create: www: failed: The brick gluster01:/srv/www is a mount point. Please create a sub-directory under the mount point and use that as the brick directory. Or use 'force' at the end of the command if you want to override this behavior.''

If for some reason the filesystem is not mounted, then glusterfs might misunderstand the situation and tell the other servers that the directory is now empty, and all files would be deleted on all servers. To avoid this a directory is created under the mount point.
{{{
mkdir /srv/www/brick
}}}

=== Install ===
Install the server.
{{{
apt-get install glusterfs-server
}}}

If you are running Buster, then make the server starts automatically and start it
{{{
systemctl enable glusterd.service
service glusterd start
}}}

=== Introduce Servers ===
The glusterfs servers need to now each other. This can be done from any one server. Here we will do it from gluster01. We need to introduce the three other servers. 
{{{
gluster peer probe gluster02
gluster peer probe gluster03
}}}

=== Server Status ===
Now check that the servers were properly probed.
{{{
gluster peer status
}}}
{{{
Number of Peers: 2

Hostname: gluster02
Uuid: 031573c2-3b1f-4946-bd78-421563249db6
State: Peer in Cluster (Connected)

Hostname: gluster03
Uuid: ff5cec1c-6d7f-4db7-8676-08deff06b4d0
State: Peer in Cluster (Connected)
}}}

=== Create Volume ===
Create the gluster volume.
{{{
gluster volume create www replica 3 transport tcp gluster01:/srv/www/brick gluster02:/srv/www/brick gluster03:/srv/www/brick
}}}

=== Persistent Metadata ===
Enable consistent metadata for the volume.
{{{
gluster volume set www cluster.consistent-metadata on
gluster volume set home features.utime on
}}}

=== Start Volume ===
Finally we can start the volume.
{{{
gluster volume start www
}}}

=== Volume Status ===
Check the status of the volume.
{{{
gluster volume status
}}}
{{{
Status of volume: www
Gluster process                             TCP Port  RDMA Port  Online  Pid
------------------------------------------------------------------------------
Brick gluster01:/srv/www                    49152     0          Y       826  
Brick gluster02:/srv/www                    49152     0          Y       1355 
Brick gluster03:/srv/www                    49152     0          Y       1034 
Self-heal Daemon on localhost               N/A       N/A        Y       846  
Self-heal Daemon on gluster02               N/A       N/A        Y       1377 
Self-heal Daemon on gluster03               N/A       N/A        Y       1054 
 
Task Status of Volume www
------------------------------------------------------------------------------
There are no active volume tasks
}}}