Re: VM-Ware Backup of VM safe?

On Wed, 20 Sep 2017 17:15:36 +0200, "Klaus P. Pieper"
<kpi6288(at)gmail(dot)com> wrote:

>> -----Ursprüngliche Nachricht-----
>> Von: pgsql-general-owner(at)postgresql(dot)org [mailto:pgsql-general-
>> owner(at)postgresql(dot)org] Im Auftrag von Thomas Güttler
>> Gesendet: Mittwoch, 20. September 2017 10:03
>> An: pgsql-general(at)postgresql(dot)org
>> Betreff: [GENERAL] VM-Ware Backup of VM safe?
>>
>> We run a PostgreSQL 9.6 server in a virtual machine.
>>
>> The virtual machine is managed by the customer.
>>
>> He does backup the VM.
>>
>> Is this enough, is this safe?
>
>When you run MS SQL Server on Hyper-V / Windows, the SQL Server
>provides ist own VSS writer responding to a taking a snapshot.
>This ensures that the image oft he SQL database is in a safe
>stake when the backup is written.
>
>I am not sure about VM-Ware, but in any case I don't think that
>PostgreSQL provides anything similar to a VSS writer
>(neither on Windows nor on Linux), so the answer is most likely
>"no, it is not safe".

Vmware does not provide VSS support in the base product - it is
available if you install the Data Recovery extensions.

FWIW, Virtualbox doesn't provide VSS support either.

But VSS is needed only to copy VM files *while* they are in use. If
you snapshot the VM, the snapshot files then are read-only and can be
freely copied. As long as the backup avoids the currently active
files, there is no danger.

George