Why does `pg_lsclusters` not list my Postgres cluster?
In order to use these postgres common tools with a cluster, they need to be used consistently. You would use pg_createcluster -d /path/to/data, instead of initdb. pg_createcluster adds the cluster to postgres-common in order to facilitate these handy operations. It is a wrapper, just like pg_ctlcluster, around the lower-level tools (e.g., initdb and pg_ctl), providing access from one place to operating on all of your clusters. It also has some defaults, such as an automatically configured log location based on the cluster name. this means you don't have to use -l /var/log/my-custom.log when you're creating or starting the server.