Re: HA Setup Review

"All cloud providers have downtime and outages. Maybe this is reliable
enough for you, but just don't treat it as a guarantee." --> Very true!!

"if a network glitch, or failure of a replica, can cascade to cause failure
of primary, is that really HA?" --> Absolutely not.
But then for HA you need a replica, so now the question is if you want to
do Async or Sync.
Sync would mean impact to Primary due to n/w issues or failures but
guarantee no-to-minimum data loss,
Async would mean no impact to Primary due to n/w issues or failures but can
cause data loss due to replication lag.
If you ask the applications, they will need both .. Neither impact to
primary nor data loss. How to weigh the options in this case?

Unless there's a middle ground that I am not aware of but would love to
know more.

Thanks,
Akshay

On Tue, Apr 30, 2024 at 10:08 PM Scott Ribe <scott_ribe(at)elevated-dev(dot)com>
wrote:

> > On Apr 30, 2024, at 10:29 AM, akshay polji <akshay(dot)polji(at)gmail(dot)com>
> wrote:
> >
> > So do you think that even such a cluster with 3 node pgpool + postgresql
> (running on the same machine) Synchronous Replication (Any one out of the
> two replicas) would mean Primary DB will be at risk of degraded
> performance?
>
> All cloud providers have downtime and outages. Maybe this is reliable
> enough for you, but just don't treat it as a guarantee. The point is: if a
> network glitch, or failure of a replica, can cascade to cause failure of
> primary, is that really HA?
>
>