Hi Mads,
Please see this article a bit old now.
http://www.infostor.com/disk-arrays/skyera-raid-5-kills-ssd-arrays.html
I think you should look for AFA solutions (PureStorage - our T0 storage)
with inline deduplication and compression.
I think that RAID 6 is a bad idea.
Tomek
W dniu 2015-03-03 o 14:20, Mads Nordholm pisze:
Very useful input indeed. I think I might end up going with a more
conventional setup for starters, and then play with CEPH on the site. And
that then leads to another question: Does anybody have some input on what
RAID level to use for a more conventional storage setup? I am looking at
deploying a setup that exclusively uses SSD, so I am probably a bit more
interested in getting as many usable GBs as possible, than I am in
optimising I/O.
So far, I have been hearing people advocating RAID 10 as well as RAID 6. I
am personally leaning towards RAID 6, but I would love to get some input
from someone with more experience using these different RAID levels in
production.
--
Mads Nordholm
On Tue, Mar 3, 2015 at 7:34 PM, Vadim Kimlaychuk <[email protected]>
wrote:
Andrija,
This is my choise already -- FreeBSD + ZFS with SSD for ZIL/L2ARC
cache + NFS. Going to be at production within couple of weeks. You have
read my thoughts ! :)
Vadim.
-----Original Message-----
From: Andrija Panic [mailto:[email protected]]
Sent: Tuesday, March 03, 2015 2:25 PM
To: [email protected]
Subject: Re: Hardware question
I'm personaly having fights with CEPh used for Primary storage - I ike
CEPH VERY MUCH, but hate it at the same time (hars word, I know...)
For Primary storage - my suggestions, play arround if you like, but avoid
it at the end...till it matures better, or simply the integration with CEPH
matures better.
If you are not using 10G network and serious hardware - it's crappy
experience... SSD for Journal, etc...
It's a fight - whenever I do some maintance on CEPH I end up swetting,
clients asking why is everythgin so slow, etc...
For our next cloud, I'm going with ZFS/NFS definitively...
Be warned :)
Cheers
On 3 March 2015 at 13:15, Vadim Kimlaychuk <[email protected]>
wrote:
Mads,
CEPH is good indeed, but keep in mind that you should really
be expert at this type of SDS. There are points that are not visible
from the first look and may bring some unpleasent surprises. For
example: "default"
option for storage I have tested was to make snapshots automatically
from the files being saved to primary storage. As a consequence when
you delete VM there are artifacts (snapshots) that are connect to
deleted VM not being deleted by Cloudstack (since CS does not know they
exist).
Another point - you can't directly use it as secondary
storage. Need to set-up application server and run RadosGW.
Performance - is a big question mark here. You need NFS or iSCSI anyway.
What we haven't fully tested - disaster recovery or
malfunction simulation. You must know how to recover from all types of
the faults. It is very easy to lose everything by just doing wrong
things (or in wrong order). From my point of view Ceph is rather
complex to start together with CS. It may be easy to set up, but not so
easy to manage.
Will suggest you to run it like a year at development to make
yourself confident you can manage it.
Regards,
Vadim.
-----Original Message-----
From: Mads Nordholm [mailto:[email protected]]
Sent: Monday, March 02, 2015 8:16 PM
To: [email protected]
Subject: Re: Hardware question
Thanks a lot for your answer, Lucian. CEPH sounds like a very
interesting solution. I will have to do some more research on that.
--
Mads Nordholm
On Tue, Mar 3, 2015 at 12:32 AM, Nux! <[email protected]> wrote:
Hi Mads,
Imo, if you want that flexibility you should go with non-local storage.
CEPH is a popular choice here, but you will need 10 Gbps between
hypervisors and storage servers if you want reasonable performance.
So, if you need more storage just add more CEPH servers. Need more
compute, add more hypervisors.
HTH
Lucian
--
Sent from the Delta quadrant using Borg technology!
Nux!
www.nux.ro
----- Original Message -----
From: "Mads Nordholm" <[email protected]>
To: [email protected]
Sent: Monday, 2 March, 2015 17:19:40
Subject: Hardware question
I am planning a small Cloudstack setup (using KVM for
virtualisation)
that
will allow me to run roughly 100 VPSs with these average
requirements:
- 1 core
- 512 MB RAM
- 20 GB SSD
I am interested in input regarding a hardware configuration that
will support this, and how to best build a small setup that will
scale easily
as
I grow. Within a year or so, I expect to have more than 1,000
guest
running.
I basically need a setup that will not completely break the bank
as I
start
out, but also one that will scale well as I grow. I am
particularly concerned with being able to add only the resources I
need. If I need
more
storage, I want to be able to add only that (preferably just by
adding disks to a RAID array), and if I need more computing power,
I want to be able to add only that.
Any input greatly appreciated.
--
Mads Nordholm
--
Andrija Panić
