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