From: Mefford, Aaron (amefford_at_about-inc.com)
Date: Fri 01 Nov 2002 - 17:17:03 GMT
There was nothing that this page clarified for me. I do already understand
quotas in general and have used them for some time, albeit not on linux, but
rather on EMC, NetApp, Sun Solaris and BSD systems. I do not recall any one
of those systems requiring you to have disk space available equal to the sum
of all quotas.
I am looking at the Vservers project as a possible solution for offering
hosted virtual private servers. As part of my requirements, I have some
specific requirements with regards to disk space management. First I need a
way to guarantee that no Vserver uses more space than they have purchased,
without dedicating the same amount of disk to that vserver. Second I need
the ability to offer this same functionality to the vserver with regards to
its users, while in some cases requiring that they dedicate space for there
users and in other cases allowing them to allocate more quota then they have
purchased from me while still requiring that the vserver as a whole never
exhausts the space it has purchased from me.
Soft/Hard quotas do not solve this as I understand it, and the link offered
no additional information in that regard.
My understanding is that with vservers as it stands today I can enforce a
global per user quota, however if I allow the owners of a vserver to create
additional users, they can then create additional users and get an
additional grant of space with each additional user they create exceeding
the desired maximum for that vserver with no way to enforce a maximum disk
usage, short of using a file based file system or LVM which violates my
first need of not dedicating the space.
If I have misunderstood you capabilities please clarify. If this is not
possible or undesireable for this vserver group then I will simply look
elsewhere. Anyhow it looks like you have an excellent start on a good
project.
Cheers,
Aaron
> -----Original Message-----
> From: Herbert Poetzl [mailto:herbert_at_13thfloor.at]
> Sent: Thursday, October 31, 2002 10:43 AM
> To: vserver_at_solucorp.qc.ca
> Subject: Re: [vserver] Quotas
>
> On Thu, Oct 31, 2002 at 09:08:12AM -0700, Mefford, Aaron wrote:
> > Soft quotas might suffice, but not really what I am after. Say Joe is a
> web
> > developer who has bought a virtual server from me with 500 Mb of space.
> As
> > the service provider I want a hard quota that will not allow joe to
> exceed
> > 500 Mb, and would typically set a soft quota at 80-90% so that joe gets
> > upgrade notices prior to running out of disk. Joe has a successful web
> > development business and has 100 clients whom he has developed sites for
> and
> > offers them hosting as well. Knowing these customers will only use 1-10
> Meg
> > of actual disk as he designs there sites, yet wanting the customer to
> feel
> > comfortable that they are getting there moneys worth (every other
> provider
> > is oversubscribing as well and the apparent cost of 100M is 1/10 its
> actual
> > value) he gives each site 100M of quota. In doing this he knows that if
> one
> > of his clients logs in and fills there quota he will still have disk
> left,
> > and have the opportunity to upgrade to compensate after the fact. I
> monitor
> > my actual disk usage and by another shelf of disk whenever I reach 75%
> > usage. I have enough users that even if 10% of them decided to fill
> disk in
> > a short period of time, space would still be available.
>
> http://www.tldp.org/HOWTO/mini/Quota-5.html
>
> best,
> Herbert