[Gluster-users] Inviting comments on my plans

[Whit Blauvelt]

On Sun, Nov 18, 2012 at 07:56:36PM -0500, David Coulson wrote:

> On 11/18/12 7:53 PM, Whit Blauvelt wrote:
> >Red Hat does not support upgrades between major versions. Thus Cent OS and
> >Scientific don't either.

> I work in an Enterprise environment, and in general once a RHEL
> release goes out of support it is time to replace the hardware
> anyway - We usually stick to a 4-5yr max lifecycle for hardware,
> which fits well with the RedHat 7yr support model. Assuming you are
> running non-RHEL software, an upgrade between major versions has to
> be a complete mess, if not impossible.

Please excuse me as I go off topic perhaps. Then again, OS variant choice
can be as important as hardware choice for a Gluster environment, and we
certainly discuss hardware a lot here.

There are times when there are compelling upgrades available for the major
daemons that are the reason for a particular system's life. With Debian or
Ubuntu, upgrading to support more recent daemons is generally trivial. I've
recently upgraded several systems in place (yes, systems vital to an
enterprise) from Ubuntu 8.04 to 12.04. There can be one or two packages that
need a small fix along the way, but I've never hit a blocker. By contrast,
taking a system for a guy doing advanced Perl stuff from RH 5 to RH 6 meant
having to go through and totally rebuild the environment (several years of
accumulated customizations) on the new system. Took a few days, where a
similar upgrade over a similar span of OS evolution in Debian or Ubuntu
would take a few hours.

I've also been known to pull a drive from an old server that's been
complexly configured, shove it in new hardware, boot from it, clone the
system to new drives, and then upgrade in place. Far simpler than
reconfiguring everything on a fresh OS install - as long as the OS supports
rolling upgrades and doesn't block the path between major versions. There's
no reason your configuration work should need to be redone just because the
hardware's being replaced.

But if you're doing fairly stock stuff, and your custom configuration on top
of the OS is trivial, sure the RH way is solid. I'm not knocking RH. I
respect the hell out of the corporate culture and the quality of much of the
fundamental development work there.

The concern with a Gluster system, even with RH the developer, is that at
some point the latest Gluster won't have its prerequisites met by the
then-current RHEL 6.x. So if you're building Gluster storage and really want
to have the best Gluster version running on it, say, two years from now, it
may have advanced far beyond whatever RH is using for a kernel then (despite
backports). Or if not Gluster, other daemons which may be vital to the
enterprise use of the system may have advanced beyond RH 6.x compatibility.
Debian variants handle that better.

To each his or her own. All the major Linux variants are heavily and
successfully used in enterprise. And none is better across the board. It
depends on your niche and circumstances.

Whit