Re: [ovirt-users] Recommended gluster setup

[Alex K]

mmm, perhaps one more reason to go to simple replica 3...

Thanx,
Alex

On Fri, Sep 15, 2017 at 3:30 PM, Sahina Bose  wrote:

>
>
> On Fri, Sep 15, 2017 at 5:48 PM, Alex K  wrote:
>
>> In the replica 3 + 1 arbiter does this mean that if I loose the two nodes
>> having the normal volumes and left only with the node that has the arbiter
>> volume, I loose all data?
>>
>
> Yes!
>
>
>>
>> Thanx,
>> Alex
>>
>> On Fri, Sep 15, 2017 at 11:25 AM, Kasturi Narra 
>> wrote:
>>
>>> Hi ,
>>>
>>>yes, you are right. Since arbiter brick  has only metadata and  data
>>> for the vm has to be served from one of the other two replicas, read is
>>> slow.
>>>
>>> Arbiter is a special subset of replica 3 volumes and is aimed at
>>> preventing split-brains and providing same consistency as a normal replica
>>> 3 volume with out consuming 3x space. You could use replica 3 and no issues
>>> with that.
>>>
>>> Thanks
>>> kasturi
>>>
>>> On Fri, Sep 15, 2017 at 12:41 PM, Abi Askushi 
>>> wrote:
>>>
 Hi all,

 I see in the ovirt guides that a gluster volume replica 3 with 1
 arbiter is recommended.
 Why not simple replica 3? Is it due to the higher replication data that
 would cause performance issues?

 What I am observing is that a VM running on the server which has the
 arbiter brick has slower read performance then when the same VM runs on
 another server with a normal brick. Has anyone observed this? Is it because
 the arbiter does not have the real data on it?

 Thanx,
 Alex

 ___
 Users mailing list
 Users@ovirt.org
 http://lists.ovirt.org/mailman/listinfo/users


>>>
>>
>> ___
>> Users mailing list
>> Users@ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/users
>>
>>
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Recommended gluster setup

[Sahina Bose]

On Fri, Sep 15, 2017 at 5:48 PM, Alex K  wrote:

> In the replica 3 + 1 arbiter does this mean that if I loose the two nodes
> having the normal volumes and left only with the node that has the arbiter
> volume, I loose all data?
>

Yes!


>
> Thanx,
> Alex
>
> On Fri, Sep 15, 2017 at 11:25 AM, Kasturi Narra  wrote:
>
>> Hi ,
>>
>>yes, you are right. Since arbiter brick  has only metadata and  data
>> for the vm has to be served from one of the other two replicas, read is
>> slow.
>>
>> Arbiter is a special subset of replica 3 volumes and is aimed at
>> preventing split-brains and providing same consistency as a normal replica
>> 3 volume with out consuming 3x space. You could use replica 3 and no issues
>> with that.
>>
>> Thanks
>> kasturi
>>
>> On Fri, Sep 15, 2017 at 12:41 PM, Abi Askushi 
>> wrote:
>>
>>> Hi all,
>>>
>>> I see in the ovirt guides that a gluster volume replica 3 with 1 arbiter
>>> is recommended.
>>> Why not simple replica 3? Is it due to the higher replication data that
>>> would cause performance issues?
>>>
>>> What I am observing is that a VM running on the server which has the
>>> arbiter brick has slower read performance then when the same VM runs on
>>> another server with a normal brick. Has anyone observed this? Is it because
>>> the arbiter does not have the real data on it?
>>>
>>> Thanx,
>>> Alex
>>>
>>> ___
>>> Users mailing list
>>> Users@ovirt.org
>>> http://lists.ovirt.org/mailman/listinfo/users
>>>
>>>
>>
>
> ___
> Users mailing list
> Users@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
>
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Recommended gluster setup

[Alex K]

In the replica 3 + 1 arbiter does this mean that if I loose the two nodes
having the normal volumes and left only with the node that has the arbiter
volume, I loose all data?

Thanx,
Alex

On Fri, Sep 15, 2017 at 11:25 AM, Kasturi Narra  wrote:

> Hi ,
>
>yes, you are right. Since arbiter brick  has only metadata and  data
> for the vm has to be served from one of the other two replicas, read is
> slow.
>
> Arbiter is a special subset of replica 3 volumes and is aimed at
> preventing split-brains and providing same consistency as a normal replica
> 3 volume with out consuming 3x space. You could use replica 3 and no issues
> with that.
>
> Thanks
> kasturi
>
> On Fri, Sep 15, 2017 at 12:41 PM, Abi Askushi 
> wrote:
>
>> Hi all,
>>
>> I see in the ovirt guides that a gluster volume replica 3 with 1 arbiter
>> is recommended.
>> Why not simple replica 3? Is it due to the higher replication data that
>> would cause performance issues?
>>
>> What I am observing is that a VM running on the server which has the
>> arbiter brick has slower read performance then when the same VM runs on
>> another server with a normal brick. Has anyone observed this? Is it because
>> the arbiter does not have the real data on it?
>>
>> Thanx,
>> Alex
>>
>> ___
>> Users mailing list
>> Users@ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/users
>>
>>
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Recommended gluster setup

[Kasturi Narra]

Hi ,

   yes, you are right. Since arbiter brick  has only metadata and  data for
the vm has to be served from one of the other two replicas, read is slow.

Arbiter is a special subset of replica 3 volumes and is aimed at
preventing split-brains and providing same consistency as a normal replica
3 volume with out consuming 3x space. You could use replica 3 and no issues
with that.

Thanks
kasturi

On Fri, Sep 15, 2017 at 12:41 PM, Abi Askushi 
wrote:

> Hi all,
>
> I see in the ovirt guides that a gluster volume replica 3 with 1 arbiter
> is recommended.
> Why not simple replica 3? Is it due to the higher replication data that
> would cause performance issues?
>
> What I am observing is that a VM running on the server which has the
> arbiter brick has slower read performance then when the same VM runs on
> another server with a normal brick. Has anyone observed this? Is it because
> the arbiter does not have the real data on it?
>
> Thanx,
> Alex
>
> ___
> Users mailing list
> Users@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
>
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

[ovirt-users] Recommended gluster setup

[Abi Askushi]

Hi all,

I see in the ovirt guides that a gluster volume replica 3 with 1 arbiter is
recommended.
Why not simple replica 3? Is it due to the higher replication data that
would cause performance issues?

What I am observing is that a VM running on the server which has the
arbiter brick has slower read performance then when the same VM runs on
another server with a normal brick. Has anyone observed this? Is it because
the arbiter does not have the real data on it?

Thanx,
Alex
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users