Thread: Load balancing of write queries among health-checked nodes

Hello. I have a PostgreSQL high availability cluster with Pgpool-II, but I don't use the virtual IP feature so my
clientsdon't know which node to send queries to. DNS round-robin is not a solution because it can't distinguish between
healthyand dead nodes. 

I thought about having a Pgpool-II instance on each client (client Pgpool-II -> cluster Pgpool-II -> PostgreSQL), but
AFAIKit can't distribute write queries. I also know that libpq may have multiple nodes to connect, but I need an
advancedhealth check because a node may have connectivity but be separated from the whole cluster so it must be
considereddead. 

Is there any solution?

Among PostgreSQL instances there is only one master. But yes, each server may be considered master by the clients
becauseit's Pgpool-II will redirect write queries to the actual master. Maybe it's even better to avoid this
unnecessarytraffic between servers and decide which Pgpool-II is in front of the master on the client side, but this is
optional.

Dnia 8 października 2024 07:30:05 GMT+04:00, Ron Johnson <ronljohnsonjr@gmail.com> napisał/a:
>On Mon, Oct 7, 2024 at 11:04 PM <me+postgres@kotovalexarian.com> wrote:
>
>> Hello. I have a PostgreSQL high availability cluster with Pgpool-II, but I
>> don't use the virtual IP feature so my clients don't know which node to
>> send queries to. DNS round-robin is not a solution because it can't
>> distinguish between healthy and dead nodes.
>>
>> I thought about having a Pgpool-II instance on each client (client
>> Pgpool-II -> cluster Pgpool-II -> PostgreSQL), but AFAIK it can't
>> distribute write queries. I also know that libpq may have multiple nodes to
>> connect, but I need an advanced health check because a node may have
>> connectivity but be separated from the whole cluster so it must be
>> considered dead.
>>
>
>Isn't that multi-master clustering?
>