> What do you mean exactly by "file-system replication"?
RAID1 setup (specifically, between two disks or EBS volumes [on AWS]), using LVM.
The two disks are synchronized, so AFAIK each should be an exact copy of the data.
> Not as long as you capture the currently-active WAL files along with the database contents.
I am not that familiar with Postgresql internals, but if we have a snapshot of the file system at the time of the crash (using RAID), is there a scenario where previous WAL segments will be needed to restore the database?
Regards,
Tom
On Thu, Dec 30, 2021 at 12:20 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
Tom Korach <tom@safekeep.com> writes: > We have a Postgresql instance (0.5-4TB in size) used for development and > on-line reporting. > We do not need high-availability, but we do need: > 1. Quick disaster recovery (<1 hour) is important. > 2. Recovery from corruption of the server or mistakes.
> Will file-system replication be enough to achieve this goal?
What do you mean exactly by "file-system replication"? Something equivalent to rsync will absolutely not work against a running Postgres server, because it won't capture a consistent state of all the files. If you have (and trust) a filesystem with snapshot capabilities, it might work to take a filesystem snapshot and hold onto it long enough to rsync from the snapshot. I'm not sure about the reliability or performance implications of such a setup, though. See