Hi Nick, thanks for that. I'd been wondering about trying VMWare. I
hadn't come across proxmox - that does look interesting, and I'll
certainly give it a try. As I mentioned to Tito, because I'm trying to
set up an environment to emulate/simulate an upgrade on several
existing boxes, I have to stick as close as possible to the existing
setup, and that limits the options severely. (I've now tried loading
the dump on the ubuntu 14/mysql 5.6.37 physical box, and it loaded
without a problem: so the problem is definitely virtualbox-related.)

On Tue, 2022-10-18 at 13:57 +0200, dng@??? wrote:
> On 18-10-2022 12:52, Peter Duffy wrote:
> > Sorry, this isn't specific to devuan (although it's involved
> > indirectly) - I'm really just looking for thoughts and comments on
> > a
> > problem which has been driving me insane for the last few weeks.
> >
> > I'm trying to replicate a setup of several fairly old linux/mysql
> > systems, as part of a project to upgrade them to devuan. I was
> > trying
> > to use virtualbox VMs to do the replication (virtualbox 6.1.32).
> > First
> > VM was ubuntu 14 and percona mysql 5.6.37; second VM was devuan
> > chimaera and percona mysql 5.6.37. Each VM had 32g RAM, 1 CPU core
> > and
> > 500g disk. I had a copy of the database from one of the original
> > systems (gzipped output from mysqldump) and the first step was to
> > load
> > it into the first VM. That was when the problems started.
> >
> > Loading the dump just consisted of "gunzip -c <file> | mysql
> > <credentials and options>" - I've done it successfully on many
> > systems
> > before now. This time, the mysql client kept choking, with
> > complaints
> > that the input contained binary zeroes. That's not supposed to
> > happen -
> > mysqldump is supposed to output a file consisting of valid SQL
> > statements and comments, designed to be poured straight back into
> > mysql
> > (I've never had a problem with it before now). I tried gunzipping
> > the
> > file on the VM, and on a separate physical box with the same
> > version of
> > gunzip, then comparing the md5sums of the files: original - md5sum
> > matches; unzipped file - md5sums didn't match. I then wrote a
> > little
> > prog to scan for binary zeros, and ran it on both files: not there
> > in
> > the one done on the physical box; there in the one done on the VM.
> >
> > After tearing my hair over this for over a week and getting
> > nowhere, I
> > decided to ditch the idea of using virtualbox VMs, dug out some old
> > retired boxes, set them up to match the VMs, and tried the load on
> > the
> > first one again. This time, no problems (apart from the fact that
> > the
> > load takes forever).
> >
> > At the moment, what seems to be inescapable is that gunzipping
> > files in
> > linux on virtualbox VMs can in some cases cause file corruption.
> > Given
> > that the identical procedure works on a physical box, it seems to
> > exclude gzip itself, the shell (bash), the file system, and the
> > kernel.
> > The only thing which seems to be left is virtualbox itself.
> >
> > Has anyone else ever experienced anything else even remotely
> > similar?
> > I've not been able to find anything relevant on google. Also - has
> > anyone any preferences for virtualisation under linux: what seems
> > to be
> > the most reliable from the range of available tools to do it?
> >
> > Thoughts would be most welcome!
> >
> >
> > _______________________________________________
> > Dng mailing list
> > Dng@???
> > https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
>
> Not specific Virtualbox 6.1.32 or with Mysql but more then one
> version
> in the 6.1.x range I have experienced various problems. Like not
> starting older VM's or crashing while booting or running very slowly.
>
> I abandoned Virtualbox totally for VMWare player and that works quite
> well so far. For the bigger experiments I have a free version of
> VMware
> Esxi 6.7 server running. Proxmox looks promising too but I did not
> yet
> have time to fully test it.
>
> As a sidenote: I am running Mysql in docker containers which is much
> more flexible and easier to backup and upgrade then on bare metal or
> VM
> based servers.
>
> Grtz.
>
> Nick
>
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