"Peter Koczan" <pjkoczan@gmail.com> writes:
> Right now, we run pg_dumpall as a non-superuser,
[ raised eyebrow... ] That's never been a recommended procedure.
> The weird thing is, whenever I run this exact same command from psql as the
> backup user, it works.
Maybe you're not trying it in the same database pg_dumpall is?
regards, tom lane