Обсуждение: shutdown Postgres (standby) host causing timeout on other servers in replication

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Joanna Xu <Joanna.Xu@amdocs.com> writes:
> We have PostgreSQL master-slave replication configuration with 4 servers.
> After shutting down one standby server, we found below errors on all other 3 servers and the applications couldn't
accessthe database due to the timeout. 
> DAO-00002 datasource connection failure:Time out waiting for a DefaultDataSource
> ERROR SQLException code: 0 SQLState: null

There's no such error message, indeed nothing about "DefaultDataSource"
at all, in the community Postgres code.  I guess it's coming from some
extension or maybe some client-side replication logic.  I suggest
finding where it's coming from and then asking the appropriate authors.

            regards, tom lane

On 11/3/22 15:55, Joanna Xu wrote:

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Hi All,

 

We have PostgreSQL master-slave replication configuration with 4 servers. 

After shutting down one standby server, we found below errors on all other 3 servers and the applications couldn’t access the database due to the timeout.

DAO-00002 datasource connection failure:Time out waiting for a DefaultDataSource

ERROR SQLException code: 0 SQLState: null

 

What could be the cause of the errors?  Would anyting be helpful to prevent it from happening?

Synchronous or asynchronous replication?

Go to the database server and look in it's logs.