If you ever encounter this error message
Assertion failed for PostgreSQL Cluster cluster-name
Assertion failed on job for firstname.lastname@example.org
after creating a cluster of the name "cluster-name" it might be because somewhere the hyphen is considered invalid. Just
pg_dropcluster <version> cluster-name pg_createcluster <version> clustername
to drop and re-create the cluster without hyphen.
I created this blog entry because I could not find any reference to this specific error with this specific reason. It might be some Debian specific error as PostgreSQLs initdb command is wrapped by pg_createcluster which again isn't mentioned by PostgreSQL. Searching the web shows mostly results in context of Ubuntu and Debian.