[Gluster-devel] Introducing Heketi: Storage Management Framework with Plugins for GlusterFS volumes

[Joseph Fernandes]

LVM or Volume Manager Dependencies:
1) SNAPSHOTS: Gluster snapshots are LVM based

2) PROVISIONING and ENFORCEMENT:
As of today Gluster does not have any control on the size of the brick. It will consume the brick (xfs)mount point given
to it without checking on how much it needs to consume. LVM (or any other volume manager) will be required to do space provisioning per brick and enforce
limits on size of bricks.

3) STORAGE SEGREGATION:
LVM pools can be used to have storage segregation i.e having primary storage pools and secondary(for Gluster replica) pools,
So that we can crave out proper space from the physical disks attached to each node.
At a high level (i.e Heketi's User) disk space can be viewed as storage pools,(i.e by aggreating disk space per pool per node using glusterd)
To start with we can have Primary pool and secondary pool(for Gluster replica) , where each file serving node in the cluster participates in
these pools via the local LVM pools.

4) DATA PROTECTION:
   Further data protection using LVM RAID. Pools can be marked to have RAID support on them, courtesy of LVM RAID.
   https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Logical_Volume_Manager_Administration/raid_volumes.html

~Joe


----- Original Message -----
From: "Luis Pabon" <lpabon at redhat.com>
To: "Jeff Darcy" <jdarcy at redhat.com>
Cc: "John Spray" <john.spray at redhat.com>, storage-eng at redhat.com
Sent: Thursday, June 18, 2015 8:05:43 AM
Subject: Re: Introducing Heketi: Storage Management Framework with Plugins	for GlusterFS volumes

Currently, Heketi is setup to provide volumes to Manila which requires them to have snapshot capabilities.  AFAIK, the only way to do that is to use LVM backed bricks in GlusterFS.  Heketi itself does not depend on LVM to create bricks and can be enhanced to support LVM-less nodes.

- Luis

----- Original Message -----
From: "Jeff Darcy" <jdarcy at redhat.com>
To: "Luis Pabon" <lpabon at redhat.com>
Cc: "John Spray" <john.spray at redhat.com>, storage-eng at redhat.com
Sent: Wednesday, June 17, 2015 7:13:38 PM
Subject: Re: Introducing Heketi: Storage Management Framework with Plugins	for GlusterFS volumes

> [LP] In Manila they are called 'shares', but for simplicity, I called them
> 'volumes' as a generic mountable network file system (NFS, CIFS, GlusterFS,
> whatever). The plugin for glusterfs does create fresh "bricks" for each
> volume, but that is how glusterfs works.  The plugin creates these bricks on
> top of thinly provisioned LVs, which the plugin manages.

Does this imply a dependency on LVM?

---
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