Re: [Users] Experience with low cost NFS-Storage as VM-Storage?
On Thu, 2014-01-09 at 08:35 +0100, squadra wrote:
Right, try multipathing with nfs :)
Yes, that´s what I meant, maybe could have been more clear about that,
sorry. Multipathing (and the load-balancing it brings) is what really
separates iSCSI from NFS.
What I´d be interested in knowing is at what breaking-point, not having
multipathing becomes an issue. I mean, we might not have such a big
VM-park, about 300-400 VMs. But so far running without multipathing
using good ole' NFS and no performance issues this far. Would be good to
know beforehand if we´re headed for a wall of some sorts, and about
"when" we´ll hit it...
/K
On Jan 9, 2014 8:30 AM, "Karli Sjöberg" <Karli.Sjoberg(a)slu.se> wrote:
On Thu, 2014-01-09 at 07:10 +0000, Markus Stockhausen wrote:
> > Von: users-bounces(a)ovirt.org [users-bounces(a)ovirt.org]" im
Auftrag von "squadra [squadra(a)gmail.com]
> > Gesendet: Mittwoch, 8. Januar 2014 17:15
> > An: users(a)ovirt.org
> > Betreff: Re: [Users] Experience with low cost NFS-Storage
as VM-Storage?
> >
> > better go for iscsi or something else... i whould avoid
nfs for vm hosting
> > Freebsd10 delivers kernel iscsitarget now, which works
great so far. or go with omnios to get comstar iscsi, which is
a rocksolid solution
> >
> > Cheers,
> >
> > Juergen
>
> That is usually a matter of taste and the available
environment.
> The minimal differences in performance usually only show up
> if you drive the storage to its limits. I guess you could
help Sven
> better if you had some hard facts why to favour ISCSI.
>
> Best regards.
>
> Markus
Only technical difference I can think of is the iSCSI-level
load-balancing. With NFS you set up the network with LACP and
let that
load-balance for you (and you should probably do that with
iSCSI as well
but you don´t strictly have to). I think it has to do with a
chance of
trying to go beyond the capacity of 1 network interface at the
same
time, from one Host (higher bandwidth) that makes people try
iSCSI
instead of plain NFS. I have tried that but was never able to
achieve
that effect, so in our situation, there´s no difference. In
comparing
them both in benchmarks, there was no performance difference
at all, at
least for our storage systems that are based on FreeBSD.
/K