Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 1 Mar 2011 14:35:33 +0100
From:      Pawel Jakub Dawidek <pjd@FreeBSD.org>
To:        Bill Desjardins <bill@ethernext.com>
Cc:        freebsd-fs@freebsd.org
Subject:   Re: HAST, zvols, istgt and carp working...
Message-ID:  <20110301133533.GD2288@garage.freebsd.pl>
In-Reply-To: <AANLkTim5FRJkf_S0aSV74S=JY%2Bg1DBZLhjYW7X9C0MkP@mail.gmail.com>
References:  <AANLkTim5FRJkf_S0aSV74S=JY%2Bg1DBZLhjYW7X9C0MkP@mail.gmail.com>

next in thread | previous in thread | raw e-mail | index | archive | help

--sXc4Kmr5FA7axrvy
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Mon, Feb 28, 2011 at 10:35:24PM -0500, Bill Desjardins wrote:
[...]
> - zfs sparse volumes seem not to be working correctly via hast (???)

You have two options:
1. Connect both nodes _before_ doing any writes to HAST provider. This
   way HAST on first connect won't synchronize any data. In other case
   it will perform full synchronization which in turn will allocate
   entire ZVOL.
2. Turn on compression (lzjb) on ZVOLs. This should be very fast and
   when compression is on all-zeros blocks are turned into holes, so
   after synchronizing whole thing, you will see space in ZVOL allocated
   only for real data.

> - possible long rebuild time on large zvols?

HAST rebuild time depends on the traffic, not components size.

> my main question is if using hast to replicate a zvol is a supported
> configuration and what are the possible drawbacks? [...]

Well, you definiately can do it, but have you considered putting entire
pool on HAST device? This way you can have multiple ZVOLs, snapshots and
rollbacks.

--=20
Pawel Jakub Dawidek                       http://www.wheelsystems.com
FreeBSD committer                         http://www.FreeBSD.org
Am I Evil? Yes, I Am!                     http://yomoli.com

--sXc4Kmr5FA7axrvy
Content-Type: application/pgp-signature
Content-Disposition: inline

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.14 (FreeBSD)

iEYEARECAAYFAk1s9iUACgkQForvXbEpPzTz/wCg3cX8uPxIUnLt+tBHXvlSs2NB
5NoAoMsn12v4AMw3SZ+YWJjLDhJH8Z9p
=5H/+
-----END PGP SIGNATURE-----

--sXc4Kmr5FA7axrvy--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20110301133533.GD2288>