Re: [Xen-API] XCP and cloud storage advise needed

[Denis Cardon <denis.cardon@xxxxxxxxxxxxxxxxxxxxxx>]

Hi Clayton,

> Wouldn’t a SAS HBA be similar to an FC or hardware iSCSI HBA?  How does
> XCP deal with a hardware iSCSI or FC HBAs and LUNs?  XCP just uses CLVM,
> which in theory should be able to share any centralized block device,
> right?  Or am I totally off base here…
A few month ago I had the opportunity to set up a test drbd 
primary-primary SR by defining a shared SR on /dev/drbd0 device in the 
pool. It worked fine however I didn't follow on because of split brain 
issues when dealing with disaster recovery.
So if it can work with a /dev/drbd0 device node, then if you can have a 
/dev/sdb corresponding to one of your MD3200 LUNs on all the nodes, then 
I guess you should be able to have a shared SR.
xe sr-create shared=true device-config:device="/dev/sdb" 
name-label="SCSI-SR1" type=lvm
However you should test thoroughly your disaster recovery scenario 
before going into production.
Cheers,

Denis

> *From:*xen-api-bounces@xxxxxxxxxxxxx
> [mailto:xen-api-bounces@xxxxxxxxxxxxx] *On Behalf Of *George Shuklin
> *Sent:* Friday, September 28, 2012 2:42 PM
> *To:* xen-api@xxxxxxxxxxxxx
> *Subject:* Re: [Xen-API] XCP and cloud storage advise needed
>
> AFAIK XCP does not supports shared SCSI SR. You can try adopt SR, but
> this is not simple task and require deep understanding of some XCP
> internals.
>
> XCP can allow you to create few SR's for few hosts, but VMs on that host
> will be unmigrable (half of cloud gone). If you want to use XCP in full
> scale you need network attachable storage, NFS or ISCSI. (note: xcp-xapi
> in debian supports only NFS).
>
> On 29.09.2012 01:11, Alexander Ivanov wrote:
>
> Hello,
>
> I have rather general question about XCP - Cloud approach, not sure if
> it's appropriate here but would really appreciate any info.
>
> I'm very new to XCP and the whole Cloud approach, though I've been using
> Xen 3.4 on CentOS 5 and KVM on CentOS 6 for quite a while. Our company
> has couple of racks with mostly Dell servers using local drives as VM
> images, plus few of the servers directly attached to Dell MD3200 (this
> is basically external RAID storage that can be shared by few servers
> with HBA cards - up to 8 ports per MD3200 connected to servers by SAS
> cables - cheap alternatives to 10G iSCSI infrastructure).
>
> So, now I'm thinking about moving to Cloud infrastructure and my
> question is if there is any way to make this MD3200 (or MD1220 or
> whatever other external storage it can be using SAS - HBA instead of
> real iSCSI) available as a SR (storage resource) for my cloud? From what
> I see so far (I have installed XCP 1.4.90 with CloudStack 3.0.2) looks
> like the only way to make some resource available to several servers in
> the cloud is to use iSCSI (or NFS - basically network sharing). But I
> really hate to spend few grands on 10G NICs and 10G switch (they're
> still not cheap). If I just stick to Xen (or KVM) without the 'cloud' I
> can 'share' this external storage connected by SAS cables among 8
> servers (which is all my 'cloud') fine. Perhaps I just missing something?
>
> I would also appreciate any info from the actual users of XCP/KVM - what
> would you recommend as a 'cloud orchestration' software? Looks like
> CloudStack is best choice now (compared to OpenStack and OpenNebula)? I
> just want to make sure the solution I choose will be relevant in few
> years from now.
>
> Thank you
>
>
>
>
> _______________________________________________
>
> Xen-api mailing list
>
> Xen-api@xxxxxxxxxxxxx  <mailto:Xen-api@xxxxxxxxxxxxx>
>
> http://lists.xen.org/cgi-bin/mailman/listinfo/xen-api
>
>
>
> This body part will be downloaded on demand.

--
Denis Cardon
Tranquil IT Systems
Les Espaces Jules Verne, bâtiment A
12 avenue Jules Verne
44230 Saint Sébastien sur Loire
tel : +33 (0) 2.40.97.57.57
http://www.tranquil-it-systems.fr


_______________________________________________
Xen-api mailing list
Xen-api@xxxxxxxxxxxxx
http://lists.xen.org/cgi-bin/mailman/listinfo/xen-api