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From Alexandre Bruyere <bruyere.alexan...@gmail.com>
Subject Re: Questions on snapshots
Date Sat, 27 Oct 2018 22:05:12 GMT
Well... Sounds like the new scripters that are coming in tomorrow will come
in handy. I'll probably have them script something to pull snapshots from
KVM directly instead of going through Cloudstack.

Is there anything that would stop this from working?

On Fri, Oct 26, 2018 at 4:15 PM Andrija Panic <andrija.panic@gmail.com>
wrote:

> Yes.
>
> There are improvements being done atm, (afaik), to try to manage snapshots
> on the primary storage (for NFS and maybe CEPH, it's already implemented on
> i.e. SolidFire).
>
> Simply this is how it was working so far - snapshots are meant to be moved
> to Secondary Storage (and later can be converted to Templates, downloaded
> from SSVM, converted to volumes etc).
> I agree with you, but that is how it was implemented, I assume for
> compatibility reasons - since different Hypervisors manage things in
> different ways - you have to support different hypervisosrs, different
> storage solutions etc (it's NOT only NFS...).
>
> Cheers
>
>
> On Fri, 26 Oct 2018 at 22:08, Alexandre Bruyere <
> bruyere.alexandre@gmail.com>
> wrote:
>
> > So wait. Are you telling me that Cloudstack does a full backup of the
> > volume every time a snapshot is taken?
> >
> > What's the point of snapshots then? Making specific operations faster?
> >
> > --
> > Alexandre Bruyère
> >
> > -----Original Message-----
> > Re: Questions on snapshots
> > From: Andrija Panic <andrija.panic@gmail.com>
> > To: users <users@cloudstack.apache.org>
> > Friday, October 26, 2018 at 3:38 PM
> >
> > So :)
> >
> > 1. Snap interval - scheduled snaps are max 1h per the so called "hourly"
> > schedule - so makes sense :) You could do some automation, by creating
> > manual snapshots and deleting oldest ones via automation - i.e. you can
> > use Cloud Monkey, CLI utility that talk to API and is great for any kind
> of
> > automation, unless you talk directly to API from i.e. Python etc, via
> > HTTPS.
> >
> > 2. number of snaps: Go to Global Configuration, there is parameter
> > "snapshot.max.hourly" - and you can change it, I assume to <=24
> ...(restart
> > mgmt server and you are good),(there are similar for daily and monthly)
> >
> > Now, related to snapshots - when you decided to really use them (i.e. in
> > production) - a BIG warning - make sure to "know" what you are doing...
> > Because so far, when you create a snapshot of the volume on Primary
> Storage
> > (NFS or CEPH), there is really a snapshot that is created almost
> instantly
> > of that volume, but then the whole image (so whole image in that point in
> > time) is being copied over (qemu-img) to the Secondary Storage NFS - and
> in
> > case of too frequent snaps, or modest networking, this might at some
> point
> > throttle your network and also break some logic inside CloudStack
> > For example: I had clients that were expecting to do hourly snapshots of
> > the 2TB image (right... perhaps a too much expectation from their side)
> and
> > this can fail with timeout (in my case it was modest CEPH performance)
> > Also pay attention to schedules, so you don't have hourly snap (one of
> > hourly runs) begin at i.e. 17.00h and then you configured at same time
> > (17.00) daily (/weekly/monthly) at 17.00 (or about the same time) - those
> > later snaps will simply fail, because there is already ongoing snap on
> the
> > same volume.
> >
> > Sorry long post...
> >
> >
> > Cheers
> > Andrija
> >
> > On Fri, 26 Oct 2018 at 20:53, Alexandre Bruyere <
> > bruyere.alexandre@gmail.com
> > >
> > wrote:
> >
> > > Hello.
> > >
> > > I'm currently investigating the functions of Cloudstack, and looked
> into
> > > snapshots.
> > >
> > > As far as I can tell, the smallest possible interval for snapshots is
> one
> > > hour. Is there a way to schedule them more frequently? For my use, 5
> > > minutes snapshots would be ideal.
> > >
> > > Also, it's limiting me to 8 snapshots kept. Is it possible to keep a
> > larger
> > > number of them - whether it is by changing configurations, by some
> other
> > > mechanic or any other way?
> > >
> >
> >
> > --
> >
> > Andrija Panić
> >
> >
> > -----Original Message-----
> > Re: Questions on snapshots
> > From: Andrija Panic <andrija.panic@gmail.com>
> > To: users <users@cloudstack.apache.org>
> > Friday, October 26, 2018 at 3:38 PM
> >
>
>
> --
>
> Andrija Panić
>

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