cloudstack-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Vadim Kimlaychuk <Vadim.Kimlayc...@Elion.ee>
Subject RE: Hardware question
Date Tue, 03 Mar 2015 14:10:20 GMT
Mads,

	I would suggest you to read this article first : http://blog.zorinaq.com/?e=10  so we follow
your thoughts - either you want HW RAID (Raid - 1,0,5,6 lv) or software RAID (like Raiz1,2,
etc.).
	I don't want to stress that SW is better than HW - it all depends.  But software raid in
most cases is more flexible and better controlled.  ZFS also offers variety of options to
be set-up to fulfill your exact needs.  For example it offers snapshots on FS level and compression.
Deduplication and copies. With compression enabled for entire pool we got fantastic IO numbers,
but increased latency and CPU usage. I guess reading more articles about that file system
you will find the solution that suits you. I will stop here because this discussion goes beyond
the topic - "hardware".  :)

Vadim.

-----Original Message-----
From: Mads Nordholm [mailto:mads@nordholm.dk] 
Sent: Tuesday, March 03, 2015 3:24 PM
To: users@cloudstack.apache.org
Subject: Re: Hardware question

Now reading about ZFS, and see that it includes RAID-Z, which sounds very interesting indeed.
Don't know how to thank you guys for all the quality feedback I am getting through this list.
I greatly appreciate it.

--
Mads Nordholm

On Tue, Mar 3, 2015 at 8:20 PM, Mads Nordholm <mads@nordholm.dk> wrote:

> 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 < 
> Vadim.Kimlaychuk@elion.ee> 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:andrija.panic@gmail.com]
>> Sent: Tuesday, March 03, 2015 2:25 PM
>> To: users@cloudstack.apache.org
>> 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 
>> <Vadim.Kimlaychuk@elion.ee>
>> 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:mads@nordholm.dk]
>> > Sent: Monday, March 02, 2015 8:16 PM
>> > To: users@cloudstack.apache.org
>> > 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! <nux@li.nux.ro> 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" <mads@nordholm.dk>
>> > > > To: users@cloudstack.apache.org
>> > > > 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
>>
>
>
Mime
View raw message