[dm-devel] [PATCH] multipath-tools Consider making 'smart' the default

[Benjamin Marzinski]

On Mon, Jun 26, 2023 at 03:11:30PM +0200, Martin Wilck wrote:
> On Tue, 2023-03-21 at 09:57 +0100, Martin Wilck wrote:
> > On Mon, 2023-03-20 at 14:41 -0500, Benjamin Marzinski wrote:
> > > On Mon, Mar 20, 2023 at 03:18:37PM +0100, Martin Wilck wrote:
> > > > On Thu, 2023-03-16 at 14:47 -0700, Brian Bunker wrote:
> > > > > 
> > 
> > > > > Subsequent volumes after the first one are discovered via unit
> > > > > attentions triggering the udev rule which calls scan-scsi-
> > > > > target.
> > > > > The SCSI devices being discovered without creating the
> > > > > corresponding
> > > > > multipath devices seems to be a bad default. We would like to
> > > > > control as much as possible from the target side to dictate
> > > > > initiator
> > > > > behavior. This comes as a regression to how it previously
> > > > > worked.
> > > > > 
> > > > > Signed-off-by: Brian Bunker <brian at purestorage.com>
> > > > 
> > > > I'm fine with this, but keep in mind that distributions will
> > > > probably
> > > > override this anyway. Red Hat and SUSE have had different
> > > > defaults
> > > > for
> > > > this basically forever. At least enterprise distros won't risk
> > > > regressions because of changing defaults.
> > > > 
> > > > Ben, what's your opinion wrt the patch?
> > > 
> > > tl;dr: I think "yes" makes more sense than "smart".
> > 
> > TL;DR: I'd like to hear the "voice of the user" at this point. So if
> > anyone except Ben, Brian, and myself has read this far, please speak
> > up
> > (and read on if you have the patience)!
> > 
> 
> Well, nobody has spoken up for 3 months.
> 
> Reconsidering the past discussion, I think we shouldn't change this
> default. As argued previously, I believe that the majority of multipath
> users install some distribution package. Distros either change the
> default by patching (like SUSE and Red Hat) or keep the upstream
> default. The first class of distros won't change their defaults, so for
> them it's just extra work (modifying the downstream patches) without
> user benefit. For the second class of distros, changing the upstream
> default would cause an unexpected change in behavior for end users.
> People who compile the upstream code themselves should have the
> knowledge to set the default to suit their needs.
> 
> Thoughts? Disagreement?

I think leaving it alone makes sense.
-Ben


> 
> Martin