4:26 p.m.
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Hi Frenando,
Here is my experience, if you consider a particular hard drive as a
brick for gluster volume and it dies, i.e. it becomes not accessible
it's a huge hassle to discard that brick and exchange with another one,
since gluster some tries to access that broken brick and it's causing
(at least it cause for me) a big pain, therefore it's better to have a
RAID as brick, i.e. have RAID 1 (mirroring) for each brick, in this case
if the disk is down you can easily exchange it and rebuild the RAID
without going offline, i.e switching off the volume doing brick
manipulations and switching it back on.
Cheers
Erekle
On 08/07/2017 03:04 PM, FERNANDO FREDIANI wrote:
For any RAID 5 or 6 configuration I normally follow a simple gold rule
which gave good results so far:
- up to 4 disks RAID 5
- 5 or more disks RAID 6
However I didn't really understand well the recommendation to use any
RAID with GlusterFS. I always thought that GlusteFS likes to work in
JBOD mode and control the disks (bricks) directlly so you can create
whatever distribution rule you wish, and if a single disk fails you
just replace it and which obviously have the data replicated from
another. The only downside of using in this way is that the
replication data will be flow accross all servers but that is not much
a big issue.
Anyone can elaborate about Using RAID + GlusterFS and JBOD + GlusterFS.
Thanks
Regards
Fernando
On 07/08/2017 03:46, Devin Acosta wrote:
>
> Moacir,
>
> I have recently installed multiple Red Hat Virtualization hosts for
> several different companies, and have dealt with the Red Hat Support
> Team in depth about optimal configuration in regards to setting up
> GlusterFS most efficiently and I wanted to share with you what I learned.
>
> In general Red Hat Virtualization team frowns upon using each DISK of
> the system as just a JBOD, sure there is some protection by having
> the data replicated, however, the recommendation is to use RAID 6
> (preferred) or RAID-5, or at least RAID-1 at the very least.
>
> Here is the direct quote from Red Hat when I asked about RAID and Bricks:
> /
> /
> /"A typical Gluster configuration would use RAID underneath the
> bricks. RAID 6 is most typical as it gives you 2 disk failure
> protection, but RAID 5 could be used too. Once you have the RAIDed
> bricks, you'd then apply the desired replication on top of that. The
> most popular way of doing this would be distributed replicated with
> 2x replication. In general you'll get better performance with larger
> bricks. 12 drives is often a sweet spot. Another option would be to
> create a separate tier using all SSD’s.” /
>
> /In order to SSD tiering from my understanding you would need 1 x
> NVMe drive in each server, or 4 x SSD hot tier (it needs to be
> distributed, replicated for the hot tier if not using NVME). So with
> you only having 1 SSD drive in each server, I’d suggest maybe looking
> into the NVME option. /
> /
> /
> /Since your using only 3-servers, what I’d probably suggest is to do
> (2 Replicas + Arbiter Node), this setup actually doesn’t require the
> 3rd server to have big drives at all as it only stores meta-data
> about the files and not actually a full copy. /
> /
> /
> /Please see the attached document that was given to me by Red Hat to
> get more information on this. Hope this information helps you./
> /
> /
>
> --
>
> Devin Acosta, RHCA, RHVCA
> Red Hat Certified Architect
>
> On August 6, 2017 at 7:29:29 PM, Moacir Ferreira
> (moacirferreira(a)hotmail.com <mailto:moacirferreira@hotmail.com>) wrote:
>
>> I am willing to assemble a oVirt "pod", made of 3 servers, each with
>> 2 CPU sockets of 12 cores, 256GB RAM, 7 HDD 10K, 1 SSD. The idea is
>> to use GlusterFS to provide HA for the VMs. The 3 servers have a
>> dual 40Gb NIC and a dual 10Gb NIC. So my intention is to create a
>> loop like a server triangle using the 40Gb NICs for virtualization
>> files (VMs .qcow2) access and to move VMs around the pod (east /west
>> traffic) while using the 10Gb interfaces for giving services to the
>> outside world (north/south traffic).
>>
>>
>> This said, my first question is: How should I deploy GlusterFS in
>> such oVirt scenario? My questions are:
>>
>>
>> 1 - Should I create 3 RAID (i.e.: RAID 5), one on each oVirt node,
>> and then create a GlusterFS using them?
>>
>> 2 - Instead, should I create a JBOD array made of all server's disks?
>>
>> 3 - What is the best Gluster configuration to provide for HA while
>> not consuming too much disk space?
>>
>> 4 - Does a oVirt hypervisor pod like I am planning to build, and the
>> virtualization environment, benefits from tiering when using a SSD
>> disk? And yes, will Gluster do it by default or I have to configure
>> it to do so?
>>
>>
>> At the bottom line, what is the good practice for using GlusterFS in
>> small pods for enterprises?
>>
>>
>> You opinion/feedback will be really appreciated!
>>
>> Moacir
>>
>> _______________________________________________
>> Users mailing list
>> Users(a)ovirt.org <mailto:Users@ovirt.org>
>> http://lists.ovirt.org/mailman/listinfo/users
>
>
> _______________________________________________
> Users mailing list
> Users(a)ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________
Users mailing list
Users(a)ovirt.org
http://lists.ovirt.org/mailman/listinfo/users
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<p>Hi Frenando,</p>
<p>Here is my experience, if you consider a particular hard drive as
a brick for gluster volume and it dies, i.e. it becomes not
accessible it's a huge hassle to discard that brick and exchange
with another one, since gluster some tries to access that broken
brick and it's causing (at least it cause for me) a big pain,
therefore it's better to have a RAID as brick, i.e. have RAID 1
(mirroring) for each brick, in this case if the disk is down you
can easily exchange it and rebuild the RAID without going offline,
i.e switching off the volume doing brick manipulations and
switching it back on.<br>
</p>
<p>Cheers</p>
<p>Erekle<br>
</p>
<br>
<div class="moz-cite-prefix">On 08/07/2017 03:04 PM, FERNANDO
FREDIANI wrote:<br>
</div>
<blockquote type="cite"
cite="mid:63bac47b-afe6-0258-d3d7-e545a5004c30@upx.com">
<meta http-equiv="Content-Type" content="text/html;
charset=utf-8">
<p>For any RAID 5 or 6 configuration I normally follow a simple
gold rule which gave good results so far:<br>
- up to 4 disks RAID 5<br>
- 5 or more disks RAID 6</p>
<p>However I didn't really understand well the recommendation to
use any RAID with GlusterFS. I always thought that GlusteFS
likes to work in JBOD mode and control the disks (bricks)
directlly so you can create whatever distribution rule you wish,
and if a single disk fails you just replace it and which
obviously have the data replicated from another. The only
downside of using in this way is that the replication data will
be flow accross all servers but that is not much a big issue.</p>
<p>Anyone can elaborate about Using RAID + GlusterFS and JBOD +
GlusterFS.</p>
<p>Thanks<br>
Regards<br>
Fernando<br>
</p>
<br>
<div class="moz-cite-prefix">On 07/08/2017 03:46, Devin Acosta
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CANCGKEp4XGs0U+Qs78eEmqCNtvpLY-Azjb5DcGhZ9yiKTBEEfw@mail.gmail.com">
<style>body{font-family:Helvetica,Arial;font-size:13px}</style>
<div id="bloop_customfont"
style="color:rgb(0,0,0);margin:0px"><font
face="Input Mono"><br>
</font></div>
<div id="bloop_customfont"
style="color:rgb(0,0,0);margin:0px"><font
face="Input Mono">Moacir,</font></div>
<div id="bloop_customfont"
style="color:rgb(0,0,0);margin:0px"><font
face="Input Mono"><br>
</font></div>
<div id="bloop_customfont"
style="color:rgb(0,0,0);margin:0px"><font
face="Input Mono">I have recently installed multiple Red Hat
Virtualization hosts for several different companies, and
have dealt with the Red Hat Support Team in depth about
optimal configuration in regards to setting up GlusterFS
most efficiently and I wanted to share with you what I
learned.</font></div>
<div id="bloop_customfont"
style="color:rgb(0,0,0);margin:0px"><font
face="Input Mono"><br>
</font></div>
<div id="bloop_customfont"
style="color:rgb(0,0,0);margin:0px"><font
face="Input Mono">In general Red Hat Virtualization team
frowns upon using each DISK of the system as just a JBOD,
sure there is some protection by having the data replicated,
however, the recommendation is to use RAID 6 (preferred) or
RAID-5, or at least RAID-1 at the very least.</font></div>
<div id="bloop_customfont"
style="color:rgb(0,0,0);margin:0px"><font
face="Input Mono"><br>
</font></div>
<div id="bloop_customfont" style="margin:0px"><font
face="Input
Mono">Here is the direct quote from Red Hat when I asked
about RAID and Bricks:</font></div>
<div id="bloop_customfont" style="margin:0px"><font
face="Input
Mono"><i><br>
</i></font></div>
<div id="bloop_customfont" style="margin:0px"><font
face="Input
Mono"><i>"A typical Gluster configuration would use RAID
underneath the bricks. RAID 6 is most typical as it gives
you 2 disk failure protection, but RAID 5 could be used
too. Once you have the RAIDed bricks, you'd then apply the
desired replication on top of that. The most popular way
of doing this would be distributed replicated with 2x
replication. In general you'll get better performance with
larger bricks. 12 drives is often a sweet spot. Another
option would be to create a separate tier using all
SSD’s.” </i></font></div>
<div id="bloop_customfont"
style="margin:0px"><br>
</div>
<div id="bloop_customfont" style="margin:0px"><font
face="Input
Mono"><i>In order to SSD tiering from my understanding you
would need 1 x NVMe drive in each server, or 4 x SSD hot
tier (it needs to be distributed, replicated for the hot
tier if not using NVME). So with you only having 1 SSD
drive in each server, I’d suggest maybe looking into the
NVME option. </i></font></div>
<div id="bloop_customfont" style="margin:0px"><font
face="Input
Mono"><i><br>
</i></font></div>
<div id="bloop_customfont" style="margin:0px"><font
face="Input
Mono"><i>Since your using only 3-servers, what I’d probably
suggest is to do (2 Replicas + Arbiter Node), this setup
actually doesn’t require the 3rd server to have big drives
at all as it only stores meta-data about the files and not
actually a full copy. </i></font></div>
<div id="bloop_customfont" style="margin:0px"><font
face="Input
Mono"><i><br>
</i></font></div>
<div id="bloop_customfont" style="margin:0px"><font
face="Input
Mono"><i>Please see the attached document that was given to
me by Red Hat to get more information on this. Hope this
information helps you.</i></font></div>
<div id="bloop_customfont" style="margin:0px"><font
face="Input
Mono"><i><br>
</i></font></div>
<br>
<div id="bloop_sign_1502087376725469184"
class="bloop_sign"><span
style="font-family:'helvetica
Neue',helvetica;font-size:14px">--</span><br
style="font-family:'helvetica
Neue',helvetica;font-size:14px">
<div class="gmail_signature"
style="font-family:'helvetica
Neue',helvetica;font-size:14px">
<div dir="ltr">
<div><br>
</div>
<div>Devin Acosta, RHCA, RHVCA</div>
<div>Red Hat Certified Architect</div>
</div>
</div>
</div>
<br>
<p class="airmail_on">On August 6, 2017 at 7:29:29 PM, Moacir
Ferreira (<a href="mailto:moacirferreira@hotmail.com"
moz-do-not-send="true">moacirferreira(a)hotmail.com</a>)
wrote:</p>
<blockquote type="cite" class="clean_bq"><span>
<div dir="ltr">
<div>
<title></title>
<div id="divtagdefaultwrapper"
style="font-size:12pt;color:#000000;font-family:Calibri,Helvetica,sans-serif"
dir="ltr">
<p><span>I am willing to assemble a oVirt "pod",
made
of 3 servers, each with 2 CPU sockets of 12 cores,
256GB RAM, 7 HDD 10K, 1 SSD. The idea is to use
GlusterFS to provide HA for the VMs. The 3 servers
have a dual 40Gb NIC and a dual 10Gb NIC. So my
intention is to create a loop like a server
triangle using the 40Gb NICs for virtualization
files (VMs .qcow2) access and to move VMs around
the pod (east /west traffic) while using the 10Gb
interfaces for giving services to the outside
world (north/south traffic).</span></p>
<p><br>
</p>
<p>This said, my first question is: How should I
deploy GlusterFS in such oVirt scenario? My
questions are:</p>
<p><br>
</p>
<p>1 - Should I create 3 RAID (i.e.: RAID 5), one on
each oVirt node, and then create a GlusterFS using
them?</p>
<p>2 - Instead, should I create a JBOD array made of
all server's disks?</p>
<p>3 - What is the best Gluster configuration to
provide for HA while not consuming too much disk
space?<br>
</p>
<p>4 - Does a oVirt hypervisor pod like I am planning
to build, and the virtualization environment,
benefits from tiering when using a SSD disk? And
yes, will Gluster do it by default or I have to
configure it to do so?</p>
<p><br>
</p>
<p>At the bottom line, what is the good practice for
using GlusterFS in small pods for enterprises?<br>
</p>
<p><br>
</p>
<p>You opinion/feedback will be really appreciated!</p>
<p>Moacir<br>
</p>
</div>
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moz-do-not-send="true">http://lists.ovirt.org/mailman/listin...
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</div>
</span></blockquote>
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