after apt update: Warning: No existing cluster is suitable as a default target.

[Brian Thompson]

On Sun, 2021-08-01 at 11:22 +0200, robert rottermann wrote:
> Hi there
> 
> i am on  a Ubuntu 16.04:
> 
> my postgresql was not updated in a while due to an error in the apt
> configuration.

How was apt misconfigured?

> After fixing it postgres13 was install, but now I get:
> 
> root at alice2 /etc/apt # psql
> Warning: No existing cluster is suitable as a default target. Please
> see man 
> pg_wrapper(1) how to specify one.
> psql: error: could not connect to server: No such file or directory
>      Is the server running locally and accepting
>      connections on Unix domain socket
> "/var/run/postgresql/.s.PGSQL.5432"?

Do you have the postgres service running?

> pg_lsclusters shows:
> Ver Cluster Port Status Owner    Data directory               Log file
> 9.5 main    5433 online postgres /var/lib/postgresql/9.5/main 
> /var/log/postgresql/postgresql-9.5-main.log
> 9.6 main    5434 online postgres /var/lib/postgresql/9.6/main 
> /var/log/postgresql/postgresql-9.6-main.log
> 13  main    5435 online postgres /var/lib/postgresql/13/main 
> /var/log/postgresql/postgresql-13-main.log
> 
> how can I fix that?

Start the postgres service and see if the errors still persist.

-- 
Brian T.