Re: Database migration across different operating systems

On Tue, Jan 8, 2019, 2:28 AM Natalie Wenz <nataliewenz(at)gmail(dot)com wrote:

> We are in an unusual circumstance, where we need to move all of our
> Postgres 10 databases from their homes on servers running FreeBSD 11 with
> ZFS to servers in another data center running Red Hat Linux 7.6 (also with
> ZFS), with minimal downtime.
>
> I understand that the recommended, safest, approach would be to
> dump/restore. We intend to do that wherever possible.
>
> However, we have some databases that require high availability/minimal
> downtime that are also very large. (50 TB, for example)
>
> Because we use ZFS on all of our current FreeBSD database hosts, one idea
> that we are exploring is to use filesystem replication to move the data
> ahead of time, and keep it in sync. Then we could start the databases on
> the Linux hosts at any time and it would be up to date. With that option,
> there’s almost no downtime.
>
> We’ve tested this procedure on a small database, and it starts, it runs,
> returns queries. There seems to be no issues.
>
> Is this a reasonable approach? Are there any known concerns/things to
> investigate before choosing this course?
>
> If it helps:
> The cpu architecture is the same on both hosts, and we’ll be running
> Postgres with the same version and same build options.
>
> Many thanks,
> Natalie
>